[clang-tools-extra] [clang-tidy] add modernize-use-constexpr check (PR #146553)

[Julian Schmidt via cfe-commits]

5chmidti wrote:

> > hopefully addressed all outstanding review comments
> 
> Did you have a chance to add C23 support? (And by extension Objective-C, which is what most of my code is :))

I have not yet added C23 support, but what I had read-up on, it seemed to be straight-forward to do.

> And by extension Objective-C

o.O :) I got no clue about Objective-C

https://github.com/llvm/llvm-project/pull/146553