[libcxx-commits] [libcxx] [llvm] [libc++] Move some macOS CI jobs to Github actions (PR #89083)

[Louis Dionne via libcxx-commits]

ldionne wrote:

I looked at the policy for Github Actions runner minutes here: https://docs.github.com/en/billing/managing-billing-for-github-actions/about-billing-for-github-actions#about-billing-for-github-actions. For public repositories, there is no limit of minutes per month. There is a maximum of 5 macOS runners at a time which could be a problem for capacity if we want to start spinning a lot more macOS CI jobs. However, I would cross that bridge when we get to it.

In particular, the goal of this transition is to move away from the MacMiniVault macOS runners we're currently using for BuildKite because they are very tedious to keep up-to-date. I'd like to avoid setting up and maintaining Github-hosted runners on those machines since that would defeat the main benefit of moving to Github actions.

@tstellar Are you fine with me landing this patch and then figuring out how to best address capacity issues if we have them? In the short term, one benefit of landing this patch is that we could eventually let go some of the machines we have in MacMiniVault (I think we can let go the two arm64 machines).

https://github.com/llvm/llvm-project/pull/89083