Fix version warning banner on the stable documentation page

[betatim]

Describe the issue linked to the documentation

Currently https://scikit-learn.org/stable/index.html shows the version warning banner ("This are the docs for an unstable version").

I think this is happening because we haven't updated https://scikit-learn.org/dev/_static/versions.json which lists all the available versions and declares which is the stable version.

This file is generated by build_tools/circle/list_versions.py which should run as part of the CI on main. My guess as to why the file hasn't been updated is that we have not merged a PR since releasing v1.5.0. If I run the script locally it generates the correct content for the .json file.

Suggest a potential alternative/fix

I think the fix is to merge any PR into main as this will regenerate the versions.json file.

This is because all versions of the documentation read the versions from the same URL, which is based on /dev/.

[betatim]

Let's see if merging #29071 fixed this

[betatim]

Looks like this is now fixed 🎉

[betatim]

For the next release we need to figure out how we perform the update of versions.json without having to merge a "random" PR.

[lesteve]

This seems fixed indeed, thanks for noticing and opening an issue!

[adrinjalali]

cc @Charlie-XIAO

[Charlie-XIAO]

For the next release we need to figure out how we perform the update of versions.json without having to merge a "random" PR.

What about #29077 instead of a "random" PR? If I'm not mistaken updating SECURITY.md is the last step of a release process and should be done except for RC. Such a PR should also be quick to review and merge.