[clang-tools-extra] [clang-tidy] Fix readability-identifier-naming FP with DefaultCase on function templates (PR #189788)

[Victor Chernyakin via cfe-commits]

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@@ -270,6 +273,9 @@ class RenamerClangTidyVisitor
   }
 
   bool VisitNamedDecl(NamedDecl *Decl) {
+    if (isa<TypeAliasTemplateDecl>(Decl))
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localspook wrote:

Would it make sense to also skip over `FunctionTemplateDecl`, `ClassTemplateDecl`, and `VarTemplateDecl`? I think this is effectively what the check was doing before the default naming style option was added.

https://github.com/llvm/llvm-project/pull/189788