[clang] [clang] fix infinite recursion (PR #143244)

[Mariya Podchishchaeva via cfe-commits]

https://github.com/Fznamznon commented:

Thank you for the fix, this overall lg. But perhaps a release note makes sense, and I agree with @Sirraide that canonical types need to be stored into the set.

https://github.com/llvm/llvm-project/pull/143244