[llvm] [GitHub] Add basic CI for libclang Python binding unit tests (PR #76784)

[Aiden Grossman via llvm-commits]

https://github.com/boomanaiden154 commented:

I'm not totally opposed to this change right now, especially since it will probably trigger pretty rarely, but we're building a lot of llvm/clang here. Caching will help, but Github's default caching rules are fairly restrictive on reuse.

We definitely want to have coverage for this, but we might not be ready *yet*. Ideally we'd be able to reuse all the clang build artifacts across multiple tests, but most of the CI is still stuck in buildkite. There also aren't any self hosted runners that have been migrated over yet.

https://github.com/llvm/llvm-project/pull/76784