[clang] [clang] fix broken canonicalization of DeducedTemplateSpecializationType (PR #95202)

[Chuanqi Xu via cfe-commits]

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@@ -1770,6 +1770,10 @@ class ASTContext : public RefCountedBase<ASTContext> {
   QualType getDeducedTemplateSpecializationType(TemplateName Template,
                                                 QualType DeducedType,
                                                 bool IsDependent) const;
+  QualType getDeducedTemplateSpecializationTypeInternal(TemplateName Template,
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ChuanqiXu9 wrote:

Given it is called `*Internal`, it might be better to give it a private access.

https://github.com/llvm/llvm-project/pull/95202