Hotfix `chunk_length_s` instead of `_ms`.
Author: Narsil
Pull request: yes

And fixes issue that the filled in token was the padded_token which could lead to incorrect decoding.
Using the same token for CTC is better (prevent extra repetition)

# What does this PR do?

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Fixes # (issue)

@patrickvonplaten

## Before submitting
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Comments:
Feel free to merge as soon as the tests are passing :-)