[Clang][Sema] fix a bug on template partial specialization (#89862)

attempt to fix
https://github.com/llvm/llvm-project/issues/68885#issuecomment-1764201896


Deduction of NTTP whose type is `decltype(auto)` would create an
implicit cast expression to dependent type and makes the type of primary
template definition (`InjectedClassNameSpecialization`) and its partial
specialization different. Prevent emitting cast expression to make clang
knows their types are identical by removing `CTAK == CTAK_Deduced` when
the type is `decltype(auto)`.

Co-authored-by: huqizhi <836744285@qq.com>