Revert "Reapply "[Clang][CWG1815] Support lifetime extension of temporary...

Revert "Reapply "[Clang][CWG1815] Support lifetime extension of temporary created by aggregate initialization using a default member initializer" (#92527)" (#94600)

Reverting due to
https://github.com/llvm/llvm-project/pull/92527#issuecomment-2149120420.

This reverts commit f049d72a

.

Co-authored-by: Bogdan Graur <bgraur@google.com>