[clang] [clang][C23] Support N3029 Improved Normal Enumerations (PR #103917)

[Mariya Podchishchaeva via cfe-commits]

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@@ -1,23 +1,23 @@
-// RUN: %clang_cc1 -triple %itanium_abi_triple %s -fsyntax-only -verify -pedantic
+// RUN: %clang_cc1 -triple %itanium_abi_triple %s -fsyntax-only -verify=expected,c99 -pedantic
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Fznamznon wrote:

Hmm, I think removing the prefix is more accurate to make the intent more clear. I don't know why I named it c99, the idea was to test not C23. I renamed it accordingly. 

https://github.com/llvm/llvm-project/pull/103917