[clang] [Clang] Fixed a crash when __PRETTY_FUNCTION__ or __FUNCSIG__ (clang-cl) appears in the trailing return type of the lambda (PR #122611)

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https://github.com/cor3ntin approved this pull request.

LGTM (but i reworded the comment slightly)

https://github.com/llvm/llvm-project/pull/122611