[clang-tools-extra] [clang-tidy] Improve readability-enum-initial-value diagnostic message (PR #176485)

[via cfe-commits]

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@@ -15,6 +15,7 @@
 #include "clang/Basic/SourceLocation.h"
 #include "llvm/ADT/STLExtras.h"
 #include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/SmallVector.h"
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zeyi2 wrote:

The coding standard says we should `#include as little as possible` ([link](https://llvm.org/docs/CodingStandards.html#minimal-list-of-includes)), so IMO we'd better follow the standard :)

https://github.com/llvm/llvm-project/pull/176485