CI: Update web and docs to OVH with the right structure
- [X] closes #32303

I'm uploading all the docs from the NumFOCUS server to the OVH (manually). And I'm changing the CI in this PR to upload the website and the dev docs to the server automatically.

I'll have a look and see if we can upload a new version of the docs automatically to OVH when a new GitHub release is generated. So, we never need to upload the website manually.

After merging this PR, and when we're confident this is working well, we'll have to redirect pandas.pydata.org to the OVH server. The dev docs will be available at pandas.pydata.org/pandas-docs/dev/ (and we can stop using pandas.io and dev.pandas.io).