[clang] [clang-tools-extra] [clang-tidy] fix match for binaryOperator in ExprMutationAnalyzer for misc-const-correctness (PR #70559)

[Piotr Zegar via cfe-commits]

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@@ -308,6 +308,11 @@ Changes in existing checks
   <clang-tidy/checks/misc/const-correctness>` check to avoid false positive when
   using pointer to member function.
 
+- Improved :doc:`misc-const-correctness
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PiotrZSL wrote:

there is already entry for this check, just merge changes.

https://github.com/llvm/llvm-project/pull/70559