Backport PR #18374 on branch v7.1.x (Bump OpenAstronomy/github-actions-workflows from 1.16.0 to 2.1.0 in /.github/workflows in the actions group) - #18377

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@pllim backporting this without a release note isn't ideal in my opinion. See #18159 (comment)

Oh ooops sorry! Do you have a preference? Should be no problem to revert but it does bloat up the history if you plan to add it back in anyway. Would adding a note make more sense at this point? Hope you can advise. Thanks!

#18159 has that note, I think it makes sense to backport it too, if you agree to it. I just want us to coordinate the move before I change #18159 (the note was originally meant for 7.2.0)

OK let's talk there.

Backport of change log for this backport at #18684