Limit uploading JSONs to trunk (#69385)
Summary:
Mac workflows on forked PRs don't have the right permissions to upload artifacts :/
Pull Request resolved: https://github.com/pytorch/pytorch/pull/69385
Reviewed By: malfet, atalman
Differential Revision: D32843252
Pulled By: janeyx99
fbshipit-source-id: e137a6707fe46559771b9d77fbfe44b0a21c914a
