[Json configs] Make json prettier for all saved tokenizer files & ensure same json format for all processors (tok + feat_extract)
Author: patrickvonplaten
Pull request: yes

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Comments:
_The documentation is not available anymore as the PR was closed or merged._

@julien-c @sgugger do you think it could make sense to make a huge automated PR creation to correct all tokenizer configs? Or maybe too much given that we have 80,000 checkpoints?

Don't think it's possible to break anything, but still not sure if it makes sense

would be a good stress test i guess =)