[clang-tools-extra] [clang-tidy] Add avoid-pragma-once. (PR #140388)

[Baranov Victor via cfe-commits]

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@@ -0,0 +1,5 @@
+// RUN: %check_clang_tidy %s portability-avoid-pragma-once %t \
+// RUN:   -- --header-filter='.*' --  -I%S/Inputs/avoid-pragma-once
+
+#include "lib.h"
+// CHECK-MESSAGES: lib.h:1:1: warning: Avoid pragma once.
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vbvictor wrote:

Please add a newline

https://github.com/llvm/llvm-project/pull/140388