[clang] [Clang][Sema] Make UnresolvedLookupExprs in class scope explicit specializations instantiation dependent (PR #100392)

[via cfe-commits]

cor3ntin wrote:

> This sounds more like an unrelated refactoring change. I'm going to hold off on doing that in this patch.
With this change, some of modified functions get multiple boolean back to back and we are for some of them at 11+ parameters. I think some cleanup would be in order
WDYT @AaronBallman ?

https://github.com/llvm/llvm-project/pull/100392