[Community notebooks] Add Wav2Vec notebook for creating captions for YT Clips
Author: Muennighoff
Pull request: yes

# What does this PR do?

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Adds a notebook for performing inference with wav2vec. The notebook aims to serve as a reference for people wanting to use wav2cec to build useful audio applications.
Includes:
- Extracting audio from movies
- Preparing audio for tokenization
- Wav2Vec inference 


## Before submitting
- [X] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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Models:

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Comments:
Very nice! @patil-suraj do you want to give this a look and merge if it looks good to you too?

Very cool! LGTM, thanks a lot for adding this!