private boolean moreThanOneConfigServer() {
        return ! getOtherConfigServersInCluster(applicationRepository.configserverConfig()).isEmpty();
    }
Maintenance jobs of the config server.
Each maintenance job is a singleton instance of its implementing class, created and owned by this,
and running its own dedicated thread.

@author hmusum
configserver/src/main/java/com/yahoo/vespa/config/server/maintenance/ConfigServerMaintenance.java