[clang] [Clang][Sema] Fix a bug on template partial specialization with issue on deduction of nontype tempalte parameter (PR #90376)

[Vlad Serebrennikov via cfe-commits]

https://github.com/Endilll commented:

`Sema.h` changes look good to me.

https://github.com/llvm/llvm-project/pull/90376