Following the practices of many other projects, we make old release notes (release tours; but not changelogs) part of the normal documentation available on the GitHub Releases.

This is one more step to getting rid of the wiki.

Related: #31415 GH Actions workflow that deploys built documentation

CC: @slel

Component: documentation

Issue created by migration from https://trac.sagemath.org/ticket/31533