[libc++abi] Add a clang-tidy config and test (#207324)

This essentially copies the `.clang-tidy` file from libc++ into
libc++abi, except that the naming conventions are updated to not add
underscores and some checks are disabled that don't pass currently. They
will be fixed in follow-ups.

GitOrigin-RevId: 3a809f644c863a17ac665e19d7dcbf7209688d18