[clang-tools-extra] [clang-tidy] Support find for string-like classes in readability-container-contains (PR #157243)

[Nicolas van Kempen via cfe-commits]

================
@@ -263,6 +263,10 @@ Changes in existing checks
   <clang-tidy/checks/portability/template-virtual-member-function>` check to
   avoid false positives on pure virtual member functions.
 
+- Improved :doc:`readability-container-contains
+  <clang-tidy/checks/readability/container-contains>` to support string
+  comparisons to ``npos``.
----------------
nicovank wrote:

Preferred a simplified statement. Let me know.

https://github.com/llvm/llvm-project/pull/157243