[clang-tools-extra] [clang-tidy][NFC] Use universal utility mock in testcases [1/N] (PR #185431)

[via cfe-commits]

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@@ -1,13 +1,8 @@
-// RUN: %check_clang_tidy %s bugprone-forwarding-reference-overload %t
+// RUN: %check_clang_tidy %s bugprone-forwarding-reference-overload %t -- -- -isystem %clang_tidy_headers
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zeyi2 wrote:

I'll update the PR after #185442 is merged, thanks :)

https://github.com/llvm/llvm-project/pull/185431