[clang] [Docs][Clang] Missing DR status for C++23-era papers in cxx_status.html (PR #68846)

[Vlad Serebrennikov via cfe-commits]

Endilll wrote:

Thank you for updating our status page!

The following papers were applied as defect reports. Have you considered them?
N4891: P2156 (Allow Duplicate Attributes) 
N4916: P2280 (Using unknown pointers and references in constant expressions)

I agree with your analysis in "Unchanged" section. As for [P2460R2 Relax requirements on `wchar_t` to match existing practices](https://wg21.link/p2460r2), it indeed seem like a pure wording change, but I'm not sure as well. Maybe @cor3ntin has an opinion on this.

https://github.com/llvm/llvm-project/pull/68846