Remove unused allowed_extensions param
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/datasets/pr_6135). All of your documentation changes will be reflected on that endpoint. <details>
<summary>Show benchmarks</summary>

PyArrow==8.0.0

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.009055 / 0.011353 (-0.002298) | 0.008835 / 0.011008 (-0.002173) | 0.117048 / 0.038508 (0.078540) | 0.096268 / 0.023109 (0.073159) | 0.474678 / 0.275898 (0.198780) | 0.550509 / 0.323480 (0.227029) | 0.005552 / 0.007986 (-0.002434) | 0.004315 / 0.004328 (-0.000013) | 0.094336 / 0.004250 (0.090086) | 0.061945 / 0.037052 (0.024892) | 0.461422 / 0.258489 (0.202933) | 0.521271 / 0.293841 (0.227430) | 0.049116 / 0.128546 (-0.079430) | 0.015007 / 0.075646 (-0.060639) | 0.414351 / 0.419271 (-0.004920) | 0.137520 / 0.043533 (0.093987) | 0.465627 / 0.255139 (0.210488) | 0.537244 / 0.283200 (0.254044) | 0.068577 / 0.141683 (-0.073106) | 1.921373 / 1.452155 (0.469219) | 2.506653 / 1.492716 (1.013937) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.273970 / 0.018006 (0.255963) | 0.750295 / 0.000490 (0.749805) | 0.004241 / 0.000200 (0.004041) | 0.000128 / 0.000054 (0.000073) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.033793 / 0.037411 (-0.003618) | 0.105562 / 0.014526 (0.091037) | 0.131771 / 0.176557 (-0.044786) | 0.196890 / 0.737135 (-0.540245) | 0.119842 / 0.296338 (-0.176496) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.634881 / 0.215209 (0.419672) | 6.069221 / 2.077655 (3.991566) | 2.678765 / 1.504120 (1.174646) | 2.460309 / 1.541195 (0.919114) | 2.517579 / 1.468490 (1.049089) | 0.869558 / 4.584777 (-3.715219) | 5.407686 / 3.745712 (1.661974) | 4.920687 / 5.269862 (-0.349175) | 3.130066 / 4.565676 (-1.435611) | 0.100337 / 0.424275 (-0.323938) | 0.009615 / 0.007607 (0.002008) | 0.745275 / 0.226044 (0.519231) | 7.577890 / 2.268929 (5.308962) | 3.607887 / 55.444624 (-51.836738) | 2.922211 / 6.876477 (-3.954266) | 3.205592 / 2.142072 (1.063519) | 1.052298 / 4.805227 (-3.752929) | 0.218798 / 6.500664 (-6.281866) | 0.082137 / 0.075469 (0.006667) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 1.696551 / 1.841788 (-0.145237) | 24.946074 / 8.074308 (16.871766) | 23.114202 / 10.191392 (12.922810) | 0.220498 / 0.680424 (-0.459925) | 0.029388 / 0.534201 (-0.504813) | 0.494721 / 0.579283 (-0.084562) | 0.603085 / 0.434364 (0.168722) | 0.573093 / 0.540337 (0.032756) | 0.784937 / 1.386936 (-0.601999) |

</details>
PyArrow==latest

<details>
<summary>Show updated benchmarks!</summary>

### Benchmark: benchmark_array_xd.json

| metric | read_batch_formatted_as_numpy after write_array2d | read_batch_formatted_as_numpy after write_flattened_sequence | read_batch_formatted_as_numpy after write_nested_sequence | read_batch_unformated after write_array2d | read_batch_unformated after write_flattened_sequence | read_batch_unformated after write_nested_sequence | read_col_formatted_as_numpy after write_array2d | read_col_formatted_as_numpy after write_flattened_sequence | read_col_formatted_as_numpy after write_nested_sequence | read_col_unformated after write_array2d | read_col_unformated after write_flattened_sequence | read_col_unformated after write_nested_sequence | read_formatted_as_numpy after write_array2d | read_formatted_as_numpy after write_flattened_sequence | read_formatted_as_numpy after write_nested_sequence | read_unformated after write_array2d | read_unformated after write_flattened_sequence | read_unformated after write_nested_sequence | write_array2d | write_flattened_sequence | write_nested_sequence |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.009642 / 0.011353 (-0.001711) | 0.007551 / 0.011008 (-0.003457) | 0.085224 / 0.038508 (0.046716) | 0.099493 / 0.023109 (0.076384) | 0.503824 / 0.275898 (0.227926) | 0.546583 / 0.323480 (0.223103) | 0.006385 / 0.007986 (-0.001601) | 0.004751 / 0.004328 (0.000423) | 0.084699 / 0.004250 (0.080449) | 0.067875 / 0.037052 (0.030823) | 0.485313 / 0.258489 (0.226824) | 0.535808 / 0.293841 (0.241967) | 0.049935 / 0.128546 (-0.078611) | 0.014427 / 0.075646 (-0.061219) | 0.095531 / 0.419271 (-0.323741) | 0.068487 / 0.043533 (0.024954) | 0.502204 / 0.255139 (0.247065) | 0.514393 / 0.283200 (0.231193) | 0.037350 / 0.141683 (-0.104333) | 1.849380 / 1.452155 (0.397226) | 1.920151 / 1.492716 (0.427434) |

### Benchmark: benchmark_getitem\_100B.json

| metric | get_batch_of\_1024\_random_rows | get_batch_of\_1024\_rows | get_first_row | get_last_row |
|--------|---|---|---|---|
| new / old (diff) | 0.298363 / 0.018006 (0.280357) | 0.651555 / 0.000490 (0.651065) | 0.005910 / 0.000200 (0.005710) | 0.000103 / 0.000054 (0.000048) |

### Benchmark: benchmark_indices_mapping.json

| metric | select | shard | shuffle | sort | train_test_split |
|--------|---|---|---|---|---|
| new / old (diff) | 0.039170 / 0.037411 (0.001758) | 0.106436 / 0.014526 (0.091910) | 0.129880 / 0.176557 (-0.046677) | 0.185401 / 0.737135 (-0.551734) | 0.125732 / 0.296338 (-0.170607) |

### Benchmark: benchmark_iterating.json

| metric | read 5000 | read 50000 | read_batch 50000 10 | read_batch 50000 100 | read_batch 50000 1000 | read_formatted numpy 5000 | read_formatted pandas 5000 | read_formatted tensorflow 5000 | read_formatted torch 5000 | read_formatted_batch numpy 5000 10 | read_formatted_batch numpy 5000 1000 | shuffled read 5000 | shuffled read 50000 | shuffled read_batch 50000 10 | shuffled read_batch 50000 100 | shuffled read_batch 50000 1000 | shuffled read_formatted numpy 5000 | shuffled read_formatted_batch numpy 5000 10 | shuffled read_formatted_batch numpy 5000 1000 |
|--------|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 0.643248 / 0.215209 (0.428039) | 6.374807 / 2.077655 (4.297152) | 3.057296 / 1.504120 (1.553176) | 2.779534 / 1.541195 (1.238340) | 2.790165 / 1.468490 (1.321675) | 0.841580 / 4.584777 (-3.743197) | 5.371478 / 3.745712 (1.625766) | 4.973251 / 5.269862 (-0.296610) | 3.235817 / 4.565676 (-1.329860) | 0.097276 / 0.424275 (-0.326999) | 0.008840 / 0.007607 (0.001233) | 0.728678 / 0.226044 (0.502634) | 7.526382 / 2.268929 (5.257454) | 3.792550 / 55.444624 (-51.652074) | 3.439134 / 6.876477 (-3.437342) | 3.466626 / 2.142072 (1.324553) | 1.035894 / 4.805227 (-3.769333) | 0.211670 / 6.500664 (-6.288994) | 0.087596 / 0.075469 (0.012127) |

### Benchmark: benchmark_map_filter.json

| metric | filter | map fast-tokenizer batched | map identity | map identity batched | map no-op batched | map no-op batched numpy | map no-op batched pandas | map no-op batched pytorch | map no-op batched tensorflow |
|--------|---|---|---|---|---|---|---|---|---|
| new / old (diff) | 1.782755 / 1.841788 (-0.059033) | 25.704407 / 8.074308 (17.630099) | 23.799672 / 10.191392 (13.608280) | 0.233952 / 0.680424 (-0.446472) | 0.030810 / 0.534201 (-0.503391) | 0.505857 / 0.579283 (-0.073426) | 0.629331 / 0.434364 (0.194967) | 0.608530 / 0.540337 (0.068192) | 0.813688 / 1.386936 (-0.573248) |

</details>
</details>

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This PR removes unused `allowed_extensions` parameter from `create_builder_configs_from_metadata_configs`.