CloudBees Replication Parent 2947

Previously, HA controllers randomly adjusted the start time for scheduled builds by ~30 seconds in either direction to help distribute the work of checking for triggers across all running replicas. Regardless of which replica checks the schedule, the actual builds are always directed to the least-loaded replica. Now, scheduled builds start much closer to zero seconds past the minute, and consecutive builds are more evenly spaced, even for schedules such as * * * * * (once per minute). This change better aligns with the behavior seen in non-HA controllers. Various factors can still delay the triggering of scheduled builds or the allocation of executors after scheduling. If precise timing is required, the job itself should check the system clock and behave accordingly.