[clang-tools-extra] [clang-tidy] Add an option to treat warnings as errors (PR #128221)

[Piotr Zegar via cfe-commits]

https://github.com/PiotrZSL commented:

Release notes entry is missing.
Look into clang-tidy 20 release notes and just copy entry and adjust it.

https://github.com/llvm/llvm-project/pull/128221