Partially revert "Remove all conda 3.5 nightly configs, remove libtorch smoketests (#21380)" (#23747)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/23747
This reverts commit 6a3ebdbbc529da79125423839bf18f527a706ab8
"Remove all conda 3.5 nightly configs" but not the smoketest
removal.
Test Plan: Imported from OSS
Differential Revision: D16632992
Pulled By: ezyang
fbshipit-source-id: 5c6dcf1510b84359a1760cfa216edea610563ad5