Ability to update merge base and push while only triggering one synchronize event

[gregorymfoster]

Select Topic Area

Question

Body

Can GitHub expose a way to push a new commit to a branch and set the branch's merge base while only triggering one synchronized event? Right now, these operations often trigger two synchronize events, which in turn trigger two CI runs.

The popular stacking tool Graphite constantly updates the merge base of PRs and pushes new comments back-to-back to "restack" branches. This creates a bug for users, where their CI will sometimes double trigger.

Ask here is to expose a two-in-one operation or other workaround. Thanks in advance!