[llvm] [GitHub] Fix slow sccache install on macOS by upgrading macOS version (PR #77165)

[Craig Hesling via llvm-commits]

linux4life798 wrote:

It looks like there is some sccache / [hendrikmuhs/ccache-action]( https://github.com/hendrikmuhs/ccache-action) issue with macOS-12.

I explained the problem in https://github.com/hendrikmuhs/ccache-action/issues/174, but basically macOS-12 builds will appears to restore their cache correctly, but the build doesn't appear to be using the cache (really slow), and then it fails to get the cache stats at the end of the run. This last part causes the cache to not be saved.

I'm running an experiment with macOS-11 and macOS-12 to see if the version bump alone triggers this:

* [Build #58 with clean/deleted cache](https://github.com/linux4life798/llvm-project-ci-test/actions/runs/7435407194)
* [Build #63 using this newly generated cache](https://github.com/linux4life798/llvm-project-ci-test/actions/runs/7436439380)

https://github.com/llvm/llvm-project/pull/77165