Revert D30869803: .circleci: Skip cuda /cudnn install if existing
Test Plan: revert-hammer
Differential Revision:
D30869803 (https://github.com/pytorch/pytorch/commit/717d267e191bcc1669acad21d87ffb70e6e89b90)
Original commit changeset: 9eb3bd20875d
fbshipit-source-id: bef8d0c693696307a3be7abd5331b7fa813d754a