Make it possible to trigger all tests by pushing to ci-all/ branch (#21750)
Summary:
Pull Request resolved: https://github.com/pytorch/pytorch/pull/21750
ghimport-source-id: 4792aa5ccab7e4b54c21f23d0b78802f85bbeb8d
Differential Revision: D15819367
Pulled By: ezyang
fbshipit-source-id: db91ee727c66469ac78e59b3662f29db53a916bc
