[clang] [clang][diagnostics] Update note_constexpr_invalid_cast to use enum_select and adjust its uses (PR #130868)

[Erich Keane via cfe-commits]

erichkeane wrote:

> @erichkeane CI is happy now! For future patches, I was wondering if to separate them like this so reviews could be easier or I should just do it all in one PR.

Separate reviews would be great, I can get those done pretty quickly.

https://github.com/llvm/llvm-project/pull/130868