Error loading file audio when downloading the Common Voice dataset directly from the Hub
## Describe the bug
When loading the Common_Voice dataset, by downloading it directly from the Hugging Face hub, some files can not be opened. 

## Steps to reproduce the bug
```python
import torch
import torchaudio
from datasets import load_dataset, load_metric
from transformers import Wav2Vec2ForCTC, Wav2Vec2Processor
import re

test_dataset = load_dataset("common_voice", "it", split="test")
#test_dataset = load_dataset('csv', data_files = {'test': '/workspace/Dataset/Common_Voice/cv-corpus80/it/test.csv'})
wer = load_metric("wer")

processor = Wav2Vec2Processor.from_pretrained("joorock12/wav2vec2-large-xlsr-italian")
model = Wav2Vec2ForCTC.from_pretrained("joorock12/wav2vec2-large-xlsr-italian")
model.to("cuda")

chars_to_ignore_regex = '[\,\?\.\!\-\;\:\"\“\'\�]'
resampler = torchaudio.transforms.Resample(48_000, 16_000)
```
## Expected results
The common voice dataset downloaded and correctly loaded whit the use of the hugging face datasets library. 

## Actual results
The error is:
```python
0ex [00:00, ?ex/s]
---------------------------------------------------------------------------
RuntimeError                              Traceback (most recent call last)
<ipython-input-48-ef87f4129e6e> in <module>
      7     return batch
      8 
----> 9 test_dataset = test_dataset.map(speech_file_to_array_fn)

/opt/conda/lib/python3.8/site-packages/datasets/arrow_dataset.py in map(self, function, with_indices, with_rank, input_columns, batched, batch_size, drop_last_batch, remove_columns, keep_in_memory, load_from_cache_file, cache_file_name, writer_batch_size, features, disable_nullable, fn_kwargs, num_proc, suffix_template, new_fingerprint, desc)
   2107 
   2108         if num_proc is None or num_proc == 1:
-> 2109             return self._map_single(
   2110                 function=function,
   2111                 with_indices=with_indices,

/opt/conda/lib/python3.8/site-packages/datasets/arrow_dataset.py in wrapper(*args, **kwargs)
    516             self: "Dataset" = kwargs.pop("self")
    517         # apply actual function
--> 518         out: Union["Dataset", "DatasetDict"] = func(self, *args, **kwargs)
    519         datasets: List["Dataset"] = list(out.values()) if isinstance(out, dict) else [out]
    520         for dataset in datasets:

/opt/conda/lib/python3.8/site-packages/datasets/arrow_dataset.py in wrapper(*args, **kwargs)
    483         }
    484         # apply actual function
--> 485         out: Union["Dataset", "DatasetDict"] = func(self, *args, **kwargs)
    486         datasets: List["Dataset"] = list(out.values()) if isinstance(out, dict) else [out]
    487         # re-apply format to the output

/opt/conda/lib/python3.8/site-packages/datasets/fingerprint.py in wrapper(*args, **kwargs)
    411             # Call actual function
    412 
--> 413             out = func(self, *args, **kwargs)
    414 
    415             # Update fingerprint of in-place transforms + update in-place history of transforms

/opt/conda/lib/python3.8/site-packages/datasets/arrow_dataset.py in _map_single(self, function, with_indices, with_rank, input_columns, batched, batch_size, drop_last_batch, remove_columns, keep_in_memory, load_from_cache_file, cache_file_name, writer_batch_size, features, disable_nullable, fn_kwargs, new_fingerprint, rank, offset, disable_tqdm, desc, cache_only)
   2465                 if not batched:
   2466                     for i, example in enumerate(pbar):
-> 2467                         example = apply_function_on_filtered_inputs(example, i, offset=offset)
   2468                         if update_data:
   2469                             if i == 0:

/opt/conda/lib/python3.8/site-packages/datasets/arrow_dataset.py in apply_function_on_filtered_inputs(inputs, indices, check_same_num_examples, offset)
   2372             if with_rank:
   2373                 additional_args += (rank,)
-> 2374             processed_inputs = function(*fn_args, *additional_args, **fn_kwargs)
   2375             if update_data is None:
   2376                 # Check if the function returns updated examples

/opt/conda/lib/python3.8/site-packages/datasets/arrow_dataset.py in decorated(item, *args, **kwargs)
   2067                 )
   2068                 # Use the LazyDict internally, while mapping the function
-> 2069                 result = f(decorated_item, *args, **kwargs)
   2070                 # Return a standard dict
   2071                 return result.data if isinstance(result, LazyDict) else result

<ipython-input-48-ef87f4129e6e> in speech_file_to_array_fn(batch)
      3 def speech_file_to_array_fn(batch):
      4     batch["sentence"] = re.sub(chars_to_ignore_regex, '', batch["sentence"]).lower()
----> 5     speech_array, sampling_rate = torchaudio.load(batch["path"])
      6     batch["speech"] = resampler(speech_array).squeeze().numpy()
      7     return batch

/opt/conda/lib/python3.8/site-packages/torchaudio/backend/sox_io_backend.py in load(filepath, frame_offset, num_frames, normalize, channels_first, format)
    150                 filepath, frame_offset, num_frames, normalize, channels_first, format)
    151         filepath = os.fspath(filepath)
--> 152     return torch.ops.torchaudio.sox_io_load_audio_file(
    153         filepath, frame_offset, num_frames, normalize, channels_first, format)
    154 

RuntimeError: Error loading audio file: failed to open file common_voice_it_17415776.mp3  ```


## Environment info

- `datasets` version: 1.18.4
- Platform: Linux-5.4.0-x86_64-with-glibc2.10
- Python version: 3.8.5
- PyArrow version: 7.0.0