GitLab

* Rename index.mdx to index.md

* With saved modifs

* Address review comment

* Treat all files

* .mdx -> .md

* Remove special char

* Update utils/tests_fetcher.py
Co-authored-by: Lysandre Debut <lysandre.debut@reseau.eseo.fr>

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Co-authored-by: Lysandre Debut <lysandre.debut@reseau.eseo.fr>

Fix bug in perplexity guide calculations and update perplexity numbers.

Fix incorrect size of input for 1st strided window length in `Perplexity of fixed-length models` (#18906)

* update the PPL for stride 512

* fix 1st strided window size

* linting

* fix typo

* styling

* Reorganize doc for multilingual support

* Fix style

* Style

* Toc trees

* Adapt templates

* Fix bad examples

* Add black formatting to style_doc

* Use first nonempty line

* Put it at the right place

* Don't add spaces to empty lines

* Better templates

* Deal with triple quotes in docstrings

* Result of style_doc

* Enable mdx treatment and fix code examples in MDXs

* Result of doc styler on doc source files

* Last fixes

* Break copy from

* First try

* Update instructions

* Convert a few docs

* And another

* Last tutorials

* New syntax for colab links

* Convert a few docs

* And another

* Last tutorials

* New syntax for colab links