Fix fastrnn benchmark regression introduced by 49946 (#50517)
Summary:
Simply add missing `from typing import List, Tuple` and `from torch import Tensor`
Fixes regression introduced by https://github.com/pytorch/pytorch/pull/49946
Pull Request resolved: https://github.com/pytorch/pytorch/pull/50517
Reviewed By: gchanan
Differential Revision: D25908379
Pulled By: malfet
fbshipit-source-id: a44b96681b6121e61b69f960f81c0cad3f2a8d20
