Account for older numpy versions in #2514 (#2524)
Summary: Pull Request resolved: https://github.com/pytorch/benchmark/pull/2524
Reviewed By: kit1980
Differential Revision: D64771621
Pulled By: mikaylagawarecki
fbshipit-source-id: 545f3d528cfbe2668c8d37e98e99423cd77a8e8e
