* Translate index page to French

* Fix indent

* Fix toctree

* Replace missing file by in_translation

* Add index

* Update docs/source/fr/index.mdx

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>

---------

Co-authored-by: Sylvain Gugger <35901082+sgugger@users.noreply.github.com>