Fixing the timestamps with chunking.
Author: Narsil
Pull request: yes

# What does this PR do?

This PR fixes #15840

- Have to change the tokenization word state machine. With chunking we can have 2 chunks
  being concatenated, both containing a separate space. Hopefully this code is readable enough.
- Refactored things to keep more alignment on CTC vs CTC_WITH_LM.
- Removed a bunch of code (no more `apply_stride`).
- Added `align_to` mecanism to make sure `stride` is aligned on token space so
  that we don't have rounding errors that make an extra stride creep, and mess up the
  timestamps.
- I tested 10s chunking on a 36mn long file and the last timings held ot the second at least, so it seems to be good. ~There is still potential room for accumulation of error. Since ctc use convolution to downsample for sample space to logits space, It is regular the `logits_shape * inputs_to_logits_ratio` != `input_shape`. Even when everything is aligned. It seems the real formula is  `(logits_shape + 1) * inputs_to_logits_ratio` != `input_shape`. That means the ratio might be slightly off and the resulting timestamps could be shifted.~


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Fixes # (issue)


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Comments:
The docs for this PR live [here](https://moon-ci-docs.huggingface.co/docs/transformers/pr_15843). All of your documentation changes will be reflected on that endpoint.

```
RUN_SLOW=1 RUN_PIPELINE_TESTS=1 pytest -sv tests/pipelines/test_pipelines_automatic_speech_recognition.py

Results (614.95s):
      22 passed
       8 skipped
```

Merging since slow tests are good.