[clang] [libcxx] [clang] Preserve Qualifiers and type sugar in TemplateNames (PR #93433)

[via cfe-commits]

pcc wrote:

This commit broke the UBSan buildbot: https://lab.llvm.org/buildbot/#/builders/85/builds/24378

Can you please take a look?

https://github.com/llvm/llvm-project/pull/93433