[clang-tools-extra] [clang-tidy] Add llvm-mlir-use-after-erase check (PR #210727)

[Zeyi Xu via cfe-commits]

https://github.com/zeyi2 commented:

Sorry, my bandwidth is limited at the moment. So my current comments are mostly documentation and test nits. I'll do a more detailed review later.

https://github.com/llvm/llvm-project/pull/210727