[clang-tools-extra] [clang-tidy] Rename google-build-namespaces to misc-anonymous-namespace-in-header (PR #173484)

[Baranov Victor via cfe-commits]

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@@ -3,11 +3,6 @@
 google-build-namespaces
 =======================
 
-`cert-dcl59-cpp` redirects here as an alias for this check.
-`fuchsia-header-anon-namespaces` redirects here as an alias for this check.
-
-Finds anonymous namespaces in headers.
-
-https://google.github.io/styleguide/cppguide.html#Namespaces
-
-Corresponding cpplint.py check name: `build/namespaces`.
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vbvictor wrote:

Should be preserved here

https://github.com/llvm/llvm-project/pull/173484