Rename master to main for test-infra references (#62728)
Summary:
Reacting to the main->master switch in test-infra
Pull Request resolved: https://github.com/pytorch/pytorch/pull/62728
Reviewed By: samestep
Differential Revision: D30104777
Pulled By: janeyx99
fbshipit-source-id: a7af7dfc69fd6e02c30ad6c15808a5b32a68c587
