Allow clang-tidy warnings.
Upstream source still have some clang-tidy warnings.
We do not want to stop Android builds on clang-tidy warnings.
Bug: 252877310
Test: TIDY_EXTERNAL_VENDOR=1 make tidy-external_subset
Change-Id: Ibb076b7c9dbb3c935a9b108681a9ab459bff42ef