Revert "delete useless cast_outputs call in unary_op_impl_float_out (#120486)"
This reverts commit d053dcfa69a52e6b9f9f2ba997b6bffbc9b29bb5.
Reverted https://github.com/pytorch/pytorch/pull/120486 on behalf of https://github.com/izaitsevfb due to Fails meta internal tests ([comment](https://github.com/pytorch/pytorch/pull/120486#issuecomment-1977343125))
