[clang-tools-extra] [llvm] [MLGO] Upstream the corpus extraction tooling (PR #72319)

[Aiden Grossman via cfe-commits]

boomanaiden154 wrote:

After this lands, my plan is to work on getting CI up and running, both to run testing and also to publish the package.

https://github.com/llvm/llvm-project/pull/72319