[clang] [clang-tools-extra] [compiler-rt] [libcxx] [lld] [lldb] [llvm] [mlir] Fix SyntaxWarning messages from python 3.12 (PR #86806)

[Louis Dionne via cfe-commits]

ldionne wrote:

Can we either finish this up or close it, please? I'd like to tidy up the libc++ review queue.

https://github.com/llvm/llvm-project/pull/86806