Pin opacus to 1.5.3 on opacus_cifar10 model (#2620)
Summary:
Related to https://github.com/pytorch/pytorch/issues/154446
Pull Request resolved: https://github.com/pytorch/benchmark/pull/2620
Reviewed By: huydhn, malfet
Differential Revision: D75477504
Pulled By: atalman
fbshipit-source-id: 840eec97ff9ab9e12d4cc91bf91333a0f3247e12
