Update Dalle2_pytorch to the latest version (#1610)
Summary: Pull Request resolved: https://github.com/pytorch/benchmark/pull/1610
Reviewed By: aaronenyeshi
Differential Revision: D45485244
Pulled By: xuzhao9
fbshipit-source-id: a48edf8e1622bd7578f7c5d7d7ae18d54d242950
