cc: @scikit-learn/core-devs

Here's the issue to figure what's left and push the 0.23.2 release out.

Any volunteers to work on the release? Otherwise I'm happy to create the PR.

• update news and what's new date in master and release branch
• create tag
• update dependencies and release tag at
  https://github.com/MacPython/scikit-learn-wheels (see RELEASE 0.23.2 MacPython/scikit-learn-wheels#63)
• twine the wheels to PyPI when that's green
• https://github.com/scikit-learn/scikit-learn/releases draft
• confirm bot detected at
  https://github.com/conda-forge/scikit-learn-feedstock and wait for merge
• https://github.com/scikit-learn/scikit-learn/releases publish
• fix the binder release version in .binder/requirement.txt (see
  [MRG] More explicit binder requirements for 0.22 #15847)
• announce on mailing list and on twitter