[clang] [Clang][Modules] Fix generic lambda local capture mapping mismatch in template instantiation (PR #202248)

[Chuanqi Xu via cfe-commits]

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@@ -0,0 +1,95 @@
+// RUN: rm -rf %t
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ChuanqiXu9 wrote:

Not a formal policy, but we want such test for C++20 modules to end with .cppm instead of .cpp.

https://github.com/llvm/llvm-project/pull/202248