Fix a bug in the torch-nightly userbenchmark. (#1539)
Summary: Pull Request resolved: https://github.com/pytorch/benchmark/pull/1539
Test Plan: Workflow https://github.com/pytorch/benchmark/actions/runs/4640981826
Reviewed By: weiwangmeta
Differential Revision: D44800999
Pulled By: xuzhao9
fbshipit-source-id: 464b978b831e5494b979ae30df1bf17460a8136e
