[WIP] Add implementation of `_extract_fbank_features_batch`

[ravenouse]

What does this PR do?

Following the discussion in #27159, this PR will add implementations of _extract_fbank_features_batch for the audio models that use the spectrogram function for feature extractions.

This PR is still a WIP and it is not ready for review yet.

Before submitting

• [ ] This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
• [X] Did you read the contributor guideline, Pull Request section?
• [ ] Was this discussed/approved via a Github issue or the forum? Please add a link to it if that's the case.
• [ ] Did you make sure to update the documentation with your changes? Here are the documentation guidelines, and here are tips on formatting docstrings.
• [ ] Did you write any new necessary tests?

Who can review?

Anyone in the community is free to review the PR once the tests have passed. Feel free to tag members/contributors who may be interested in your PR.

[amyeroberts]

cc @ylacombe