Enabling automatic loading of tokenizer with `pipeline` for `audio-classification`.
Author: Narsil
Pull request: yes

# What does this PR do?

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Fixes # (issue)


## Before submitting
- [ ] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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## Who can review?

@patrickvonplaten
@LysandreJik

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag
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Models:

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Library:

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HF projects:

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Comments:
Once Lysandre views this, I'll merge.