[clang-tools-extra] [clang-tidy] Enhance modernize-use-starts-ends-with to handle substr patterns (PR #116033)

[Piotr Zegar via cfe-commits]

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@@ -7,26 +7,16 @@ Checks for common roundabout ways to express ``starts_with`` and ``ends_with``
 and suggests replacing with the simpler method when it is available. Notably, 
 this will work with ``std::string`` and ``std::string_view``.
 
-.. code-block:: c++
+The check handles the following expressions:
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PiotrZSL wrote:

avoid "The check", documentation is in context of check, write something like "Covered scenarios/expressions" or something

https://github.com/llvm/llvm-project/pull/116033