[clang] Disable alias template CTAD for C++17 (PR #133597)

[Matheus Izvekov via cfe-commits]

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@@ -113,7 +113,7 @@ namespace dependent {
   };
   template<typename T> void f() {
     typename T::X tx = 0;
-    typename T::Y ty = 0;
+    typename T::template Y<int> ty = 0;
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mizvekov wrote:

This is just removing the test. Ideally this would still be tested under C++20.

https://github.com/llvm/llvm-project/pull/133597