Only trigger remote mirror update once per push if multiple branches/tags are pushed
Problem to solve
For each branch that is pushed, BranchPushService
remote mirrors. If multiple branches are pushed we should just update the remote mirror once.
See https://gitlab.com/gitlab-org/gitlab-ce/issues/65804#note_201762495
Proposal
Only trigger remote mirror update once per push if multiple branches/tags are pushed
Edited by James Ramsay (ex-GitLab)