[llvm] [mlir] [MLIR][Python] reland (narrower) type stub generation (PR #157930)

[Jakub Kuderski via llvm-commits]

kuhar wrote:

Do distros prefer/expect to use system python packages? AFAIK, the general recommendation for MLIR-based projects is to use a virtual environment.

https://github.com/llvm/llvm-project/pull/157930