Add b2ai speaker verification functions

[ibevers]

• [x] update to not use big models in remote test
• [x] update tests to use the audio mono audio fixture

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 40.00000% with 30 lines in your changes missing coverage. Please review.

Project coverage is 63.01%. Comparing base (f3c595f) to head (a45d12e). Report is 1 commits behind head on main.

Files	Patch %	Lines
...tasks/speaker_verification/speaker_verification.py	35.00%	13 Missing :warning:
src/tests/audio/tasks/speaker_verification_test.py	40.00%	9 Missing :warning:
...enselab/audio/tasks/preprocessing/preprocessing.py	46.66%	8 Missing :warning:

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #87 +/- ## ========================================== - Coverage 63.04% 63.01% -0.03% ========================================== Files 63 65 +2 Lines 2073 2120 +47 ========================================== + Hits 1307 1336 +29 - Misses 766 784 +18 ```

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[ibevers]

@fabiocat93 would you mind reviewing this? It's the last component of b2aiprep's process module that needs to be incorporated into senselab as far as I can tell. It would also be great if we could do a minor release when we merge it to facilitate integration into b2aiprep

[fabiocat93]

hi @ibevers , i finally got the chance to review your code. i have left some comments

[ibevers]

@fabiocat93 I incorporated your feedback. Hopefully, this is mergable now:)