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

[Baranov Victor via cfe-commits]

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@@ -0,0 +1 @@
+#pragma once
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vbvictor wrote:

Missing tests where there are spaces between `#` and `pragma` and multiple spaces between `pragma` and `once`.

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