[clang] [Sema] Fix crash on invalid operator template-id (PR #181404)

[Yanzuo Liu via cfe-commits]

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@@ -0,0 +1,3 @@
+// RUN: not %clang_cc1 -fsyntax-only  %s
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zwuis wrote:

Please read <https://clang.llvm.org/docs/InternalsManual.html#testing>. `not` should not be used here.

https://github.com/llvm/llvm-project/pull/181404