[clang] [Clang][Diagnostics] Mention 'import std' in typeid diagnostic (PR #173236)

[Chuanqi Xu via cfe-commits]

https://github.com/ChuanqiXu9 commented:

LGTM generally. You can do the same thing for other headers, as `<new>` or `<coroutine>` in other PR.

https://github.com/llvm/llvm-project/pull/173236