[clang-tools-extra] [clang-tidy][NFC] add '.clang-tidy' config for clang-tidy project (PR #147793)

[Baranov Victor via cfe-commits]

vbvictor wrote:

Added all people that participated in RFC and regular clang-tidy reviewers to see this change.

https://github.com/llvm/llvm-project/pull/147793