[clang-tools-extra] [clang-tidy] Header check support for check_clang_tidy.py (PR #175735)

[Yanzuo Liu via cfe-commits]

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zwuis wrote:

Is it necessary? Release notes are for clang-tidy users, but this improvement is for clang-tidy developers.

https://github.com/llvm/llvm-project/pull/175735