docs: public static String getZooKeeperEnsemble(Configuration flinkConf)
  			throws IllegalConfigurationException {
  
  		String zkQuorum = flinkConf.getValue(HighAvailabilityOptions.HA_ZOOKEEPER_QUORUM);
  
  		if (zkQuorum == null || StringUtils.isBlank(zkQuorum)) {
  			throw new IllegalConfigurationException("No ZooKeeper quorum specified in config.");
  		}
  
  		// Remove all whitespace
  		zkQuorum = zkQuorum.replaceAll("\\s+", "");
  
  		return zkQuorum;
  	}