opus decoding error
see https://huggingface.co/datasets/stable-speech/mls_eng_10k/discussions/1#65ef6e9d440a5fc3d94a40ad

To fix this maybe we should pin `soundfile` library to `>=1.0.31` (first version that supported opus) like [we do in `datasets` library](https://github.com/huggingface/datasets/blob/main/src/datasets/config.py#L144). 

opus decoding error: see https://huggingface.co/datasets/stable-speech/mls_eng_10k/discussions/1#65ef6e9d440a5fc3d94a40ad

To fix this maybe we should pin `soundfile` library to `>=1.0.31` (first version that supported opus) like [we do in `datasets` library](https://github.com/huggingface/datasets/blob/main/src/datasets/config.py#L144). 
