[clang] [Clang] [CodeGen] Perform derived-to-base conversion on explicit object parameter in lambda (PR #89828)

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https://github.com/cor3ntin approved this pull request.

I think this makes sense. Thanks!

@Endilll just updated the list of DRs to avoid unrelated changes, so by fixing the conflict, only changes to cwg2881 should be in your PR

https://github.com/llvm/llvm-project/pull/89828