[clang-tools-extra] [clang-tidy] Add llvm-regex check (PR #207407)

[Zeyi Xu via cfe-commits]

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@@ -251,6 +251,7 @@ Clang-Tidy Checks
    :doc:`llvm-prefer-register-over-unsigned <llvm/prefer-register-over-unsigned>`, "Yes"
    :doc:`llvm-prefer-static-over-anonymous-namespace <llvm/prefer-static-over-anonymous-namespace>`,
    :doc:`llvm-redundant-casting <llvm/redundant-casting>`, "Yes"
+   :doc:`llvm-regex <llvm/regex>`, "No"
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zeyi2 wrote:

```suggestion
   :doc:`llvm-regex <llvm/regex>`,
```

https://github.com/llvm/llvm-project/pull/207407