[clang] [C] Modify -Wdefault-const-init (PR #137961)

[Mariya Podchishchaeva via cfe-commits]

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@@ -1,28 +1,23 @@
-// RUN: %clang_cc1 -fsyntax-only -verify=c,unsafe -Wdefault-const-init %s
-// RUN: %clang_cc1 -fsyntax-only -verify=c,unsafe -Wc++-compat %s
-// RUN: %clang_cc1 -fsyntax-only -verify=unsafe %s
-// RUN: %clang_cc1 -fsyntax-only -verify=c -Wdefault-const-init -Wno-default-const-init-unsafe %s
-// RUN: %clang_cc1 -fsyntax-only -verify=good -Wno-default-const-init-unsafe %s
-// RUN: %clang_cc1 -fsyntax-only -verify=cxx -x c++ %s
-// good-no-diagnostics
+
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Fznamznon wrote:

An empty line in the beginning is kind of strange
```suggestion
```

https://github.com/llvm/llvm-project/pull/137961