[clang] [Clang][Sema] Ignore previous partial specializations of member class templates explicitly specialized for a implicitly instantiated class template specialization (PR #113464)

[Erich Keane via cfe-commits]

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

Thanks for your patience, looks good to me!

https://github.com/llvm/llvm-project/pull/113464