[clang-tools-extra] [clang-tidy] Rename 'google-build-namespaces' check to 'misc-anonymous-namespace-in-header' and keep initial as alias. (PR #170986)

[Baranov Victor via cfe-commits]

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@@ -1,7 +1,6 @@
 // RUN: clang-tidy %s -checks='-*,google-build-namespaces,google-build-using-namespace' -header-filter='.*' -- | FileCheck %s -implicit-check-not="{{warning|error}}:"
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vbvictor wrote:

Please move the whole test file to `misc` and rename it "anonymous-namespace-in-header.cpp" (same as checkname)

https://github.com/llvm/llvm-project/pull/170986