[clang] [clang] Avoid crash due to unimplemented StructuralValue support in the template differ (PR #93265)

[Andrey Ali Khan Bolshakov via cfe-commits]

================

----------------
bolshakov-a wrote:

I don't see any C++26-specific stuff here, only C++20.

https://github.com/llvm/llvm-project/pull/93265