Proposal Remove the weird `inspect` in ASR pipeline and make WhisperEncoder just nice to use.
Author: Narsil
Pull request: yes

# What does this PR do?

It seems that accepting `attention_mask` is kind of an invariant of our
models. For Seq2Seq ASR models, we had a special comment on how it
actually was important to send it.

`inspecting` seems pretty brittle way to handle this case.
My suggestion is to simply add it as an kwarg that and just ignoring
it with the docstring explaining why it's ignored.



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Fixes # (issue)


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