Easy way to segment into 30s snippets given an m4a file and a vtt file 
### Feature request

Uploading datasets is straightforward thanks to the ability to push Audio to hub. However, it would be nice if the data (text and audio) could be segmented when being pushed (if not possible already).

### Motivation

It's easy to create a vtt file from an audio file. If there could be auto-segmenting, this would make the creation of datasets much faster.

### Your contribution

I have made a custom script to do this but it's not all that clean - uses librosa and pydub.