[clang] [Clang] update reasoned delete diagnostic kind to use Extension, making it pedantic only (PR #114713)

[Aaron Ballman via cfe-commits]

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@@ -49,3 +59,4 @@ struct C {
   U f = delete ("hello"); // expected-error {{cannot delete expression of type 'const char[6]'}}
 };
 }
+#endif
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AaronBallman wrote:

When you make edits, please make sure the file ends with a newline again.

https://github.com/llvm/llvm-project/pull/114713