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

[Baranov Victor via cfe-commits]

vbvictor wrote:

Based on [carlosgalvezp](https://github.com/carlosgalvezp)'s comment in https://github.com/llvm/llvm-project/pull/147902#pullrequestreview-3005674950 changed `Checks: []` to `Checks: >` to comply with older version of `clang-tidy`.

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