@Test
    void default_space_nodes_not_marked_as_maintenance_when_cluster_has_no_global_document_types() throws Exception {
        FleetControllerOptions.Builder builder = defaultOptions()
                .setClusterHasGlobalDocumentTypes(false)
                .setMasterZooKeeperCooldownPeriod(1)
                .setMinTimeBeforeFirstSystemStateBroadcast(100000);
        Timer timer = new RealTimer();
        setUpFleetControllers(3, timer, builder);
        setUpVdsNodes(timer);
        waitForMaster(0);
        waitForStableSystem();
        waitForStateInAllSpaces("version:\\d+ distributor:10 storage:10");
    }
Should always write new version to ZooKeeper, even if the version will not
be published to any nodes. External services may still observe the version
number via the cluster REST API, and we should therefore ensure that we never
risk rolling back the version number in the face of a reelection.
clustercontroller-core/src/test/java/com/yahoo/vespa/clustercontroller/core/MasterElectionTest.java