[clang-tools-extra] Add bugprone-loop-variable-copied-then-modified clang-tidy check. (PR #157213)

[Julia Hansbrough via cfe-commits]

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@@ -161,16 +161,27 @@ Improvements to clang-tidy
 New checks
 ^^^^^^^^^^
 
+- New :doc:`bugprone-derived-method-shadowing-base-method
+  <clang-tidy/checks/bugprone/derived-method-shadowing-base-method>` check.
+
+  Finds derived class methods that shadow a (non-virtual) base class method.
+ 
+ - New :doc:`bugprone-derived-method-shadowing-base-method
----------------
flowerhack wrote:

Augh, yeah, bad rebase.  I've re-pushed and I believe it's deduplicated now.

https://github.com/llvm/llvm-project/pull/157213