ci: Add single concurrency to merge / revert
Changes the merge / revert workflows to only run one job at a time
Signed-off-by: Eli Uriegas <eliuriegasfb.com>
Pull Request resolved: https://github.com/pytorch/pytorch/pull/77424
Signed-off-by: Eli Uriegas <eliuriegas@fb.com>
Approved by: https://github.com/bigfootjon, https://github.com/malfet
