[llvm] [Github] Allow CI to run different Python version tests at once (PR #102455)

[Aiden Grossman via llvm-commits]

boomanaiden154 wrote:

> On another note, now that I think about it, is there any need to actually run the build twice? Shouldn't it be sufficient to build libclang once, and then just run the Python tests with separate Python versions?

I'm not sure exactly how the bindings are setup. Given it interfaces with a C++ API, I'm guessing we're pulling in cpython headers somewhere (whether directly or indirectly) which means building against different platforms might produce different results/errors at build time. That would mean we need to build everything separately for different python versions.

https://github.com/llvm/llvm-project/pull/102455