[clang] [clang][Sema] Handle function parameter packs in `PackDeductionScope::addPacks` (PR #215235)

[Younan Zhang via cfe-commits]

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@@ -445,6 +445,8 @@ features cannot lower the translation-unit ABI level;
   affect C++26 constexpr structured bindings and expansion statements, but
   also affects some uses of plain structured bindings. (#GH211930)
 
+- Fixed an assertion during template argument deduction where a function parameter pack is referenced by other types in the function type. (GH28877, GH213760)
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zyn0217 wrote:

```suggestion
- Fixed an assertion during template argument deduction where a function parameter pack is referenced by other types in the function type. (#GH28877, #GH213760)
```

https://github.com/llvm/llvm-project/pull/215235