public void saveLatestClusterStateBundle(DatabaseContext databaseContext, ClusterStateBundle clusterStateBundle) {
        fleetControllerContext.log(logger, Level.FINE, () -> "Scheduling bundle " + clusterStateBundle + " to be saved to ZooKeeper");
        pendingStore.clusterStateBundle = clusterStateBundle;
        doNextZooKeeperTask(databaseContext);
    }
This is called to attempt the next task against ZooKeeper we want to try.

@return true if we did or attempted any work.
clustercontroller-core/src/main/java/com/yahoo/vespa/clustercontroller/core/database/DatabaseHandler.java