Init runs the task queue to that handles auto merges.

NewNotifier create a new automergeNotifier notifier.

RemoveScheduledAutoMerge cancels a previously scheduled pull request.

ScheduleAutoMerge if schedule is false and no error, pull can be merged directly.

StartPRCheckAndAutoMerge start an automerge check and auto merge task for a pull request.

StartPRCheckAndAutoMergeBySHA start an automerge check and auto merge task for all pull requests of repository and SHA.