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

[Nicolas van Kempen via cfe-commits]

================
@@ -25,6 +25,7 @@ class UseStartsEndsWithCheck : public ClangTidyCheck {
   UseStartsEndsWithCheck(StringRef Name, ClangTidyContext *Context);
   void registerMatchers(ast_matchers::MatchFinder *Finder) override;
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
+  bool isNegativeComparison(const Expr* ComparisonExpr);
----------------
nicovank wrote:

Function should be static in `.cpp` file at top of file.
```suggestion
```

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