[clang-tools-extra] [clang-tidy] Add `readability-redundant-tag` check (PR #210007)

[via cfe-commits]

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@@ -97,6 +97,11 @@ Improvements to clang-tidy
 New checks
 ^^^^^^^^^^
 
+- New :doc:`readability-redundant-tag
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EugeneZelenko wrote:

Please keep alphabetical order (by check name) and separate entries with empty line.

https://github.com/llvm/llvm-project/pull/210007