[clang] [llvm] [clang][python][test] Move python binding tests to lit framework (PR #148802)

[Jannick Kremer via llvm-commits]

DeinAlptraum wrote:

Next attempt after https://github.com/llvm/llvm-project/pull/146844.
The only change is, that I added a `UNSUPPORTED` directive for s390x after the discussion on that PR. (see comment https://github.com/llvm/llvm-project/pull/146844#issuecomment-3048291798)

https://github.com/llvm/llvm-project/pull/148802