Update GitHub Actions script

[MisterDA]

• Always use latest patch release
• Add OCaml 5.0 and 4.14
• Update to actions/checkout@v3

Subsumes #137.

[MisterDA]

I've rebased this branch and added opam-repository-mingw#sunset on Windows.

[aantron]

Thank you. Immediately before you rebased this branch, I had already merged master into it (see the commit history) and was about to squash this back into master. When you force-push, please use --force-with-lease. I'll see about what to do now -- please don't force-push in the meantime :)

[aantron]

Could you comment on why you added opam-repository-mingw#sunset? FYI the last build on Windows, in this PR but without the repo, succeeded.

[MisterDA]

Sorry about the force-push. I had forgotten about that PR, the renewed activity was an incentive to update it as I would do now.
The fdopen/opam-repository-mingw was deprecated and isn't receiving any updates. The ocaml-opam/opam-repository-mingw#sunset branch has been augmented with

• OCaml 4.14.1 packages, in the same style as the 4.14.0 forked packages (the “pre-compiled” package variants exist, but they’re not pre-compiled);
• Changes to the constraints for existing packages only.
  It is also recommended to use it as the default repository, and fallback to ocaml/opam-repository for newer packages.
  See Sunsetting opam-repository-mingw.

[aantron]

Thanks, I will look into that!

What do you mean by that this PR subsumes #137?

[MisterDA]

What do you mean by that this PR subsumes #137?

It was probably a bad choice of words.
This PR just replaces parts of #137 that were updating the GitHub Actions script. IIRC this PR and #139 completely replace #137.

[aantron]

Thank you and sorry about the delay!