Dataset JSON is incorrect
As discussed, the metadata JSON files must be regenerated because the keys were nor properly generated and they will not be read by the builder:
> Indeed there is some problem/bug while reading the datasets_info.json file: there is a mismatch with the config.name keys in the file...
In the meanwhile, in order to be able to use the datasets_info.json file content, you can create the builder without passing the name :
```
In [25]: builder = datasets.load_dataset_builder("journalists_questions")
In [26]: builder.info.splits
Out[26]: {'train': SplitInfo(name='train', num_bytes=342296, num_examples=10077, dataset_name='journalists_questions')}
```

After regenerating the metadata JSON file for this dataset, I get the right key:
```
{"plain_text": {"description": "The journalists_questions corpus (
``` Thanks!
## Describe the bug

The JSON file generated for https://github.com/huggingface/datasets/blob/573f3d35081cee239d1b962878206e9abe6cde91/datasets/journalists_questions/journalists_questions.py is https://github.com/huggingface/datasets/blob/573f3d35081cee239d1b962878206e9abe6cde91/datasets/journalists_questions/dataset_infos.json.

The only config should be `plain_text`, but the first key in the JSON is `journalists_questions` (the dataset id) instead.

```json
{
  "journalists_questions": {
    "description": "The journalists_questions corpus (version 1.0) is a collection of 10K human-written Arabic\ntweets manually labeled for question identification over Arabic tweets posted by journalists.\n",
    ...
```

## Steps to reproduce the bug

Look at the files.

## Expected results

The first key should be `plain_text`:

```json
{
  "plain_text": {
    "description": "The journalists_questions corpus (version 1.0) is a collection of 10K human-written Arabic\ntweets manually labeled for question identification over Arabic tweets posted by journalists.\n",
    ...
```

## Actual results

```json
{
  "journalists_questions": {
    "description": "The journalists_questions corpus (version 1.0) is a collection of 10K human-written Arabic\ntweets manually labeled for question identification over Arabic tweets posted by journalists.\n",
    ...
```

