[CLAP] Replace hard-coded batch size to enable dynamic ONNX export

[xenova]

What does this PR do?

This PR unblocks adding ONNX export support for CLAP models in Optimum (see PR), by replacing hard-coded batch size in the window_reverse function. This was already done in the past for other similar models (by @lewtun), but since then, CLAP was added (by @ArthurZucker), and this change was not brought across there.

Fixes huggingface/optimum#1552 (comment)

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• This PR fixes a typo or improves the docs (you can dismiss the other checks if that's the case).
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@ArthurZucker @lewtun @echarlaix

[HuggingFaceDocBuilderDev]

The docs for this PR live here. All of your documentation changes will be reflected on that endpoint.

[ArthurZucker]

LGTM thanks

[xenova]

Added back the docstring 👍 - ready to merge imo? :)

[ArthurZucker]

Yep just make style and rebase should do the trick for the CI

[xenova]

Done 👍 (failed style seemed to be unrelated; should be fixed now)

[ArthurZucker]

Thanks 👍🏻