[clang] [clang-tools-extra] [clang-tidy] Add experimental header-filter matching (PR #194370)

[Zeyi Xu via cfe-commits]

================
@@ -0,0 +1,64 @@
+//===--- HeaderFilterHelpers.h - clang-tidy header filtering ----*- C++ -*-===//
----------------
zeyi2 wrote:

```suggestion
//===----------------------------------------------------------------------===//
```

https://github.com/llvm/llvm-project/pull/194370