[clang] [clang][NFC] Refactor `clang/test/SemaCXX/type-traits.cpp` to use modern `static_assert` (PR #77584)

[Erich Keane via cfe-commits]

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@@ -2671,212 +2660,212 @@ struct has_unique_object_representations {
   static const bool value = __has_unique_object_representations(T);
 };
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erichkeane wrote:

Yep, thats true too, it was the intent at the time though (and to better emulate hte test cases we were given, note that the whole section is basically a copy/paste + de-c++17'izing of what STL gave me).

My comment on the bug has more context.

https://github.com/llvm/llvm-project/pull/77584