ZooKeeperHaServicesTest.testSimpleCloseAndCleanupAllData is unstable

11:15:11.201 [INFO] Running org.apache.flink.runtime.highavailability.zookeeper.ZooKeeperHaServicesTest
11:15:12.908 [INFO] Tests run: 23, Failures: 0, Errors: 0, Skipped: 0, Time elapsed: 9.255 s - in org.apache.flink.runtime.jobmaster.JobMasterTest
11:15:13.646 [INFO] Running org.apache.flink.runtime.highavailability.zookeeper.ZooKeeperRegistryTest
11:15:14.874 [ERROR] Tests run: 3, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 3.67 s <<< FAILURE! - in org.apache.flink.runtime.highavailability.zookeeper.ZooKeeperHaServicesTest
11:15:14.874 [ERROR] testSimpleCloseAndCleanupAllData(org.apache.flink.runtime.highavailability.zookeeper.ZooKeeperHaServicesTest)  Time elapsed: 0.132 s  <<< FAILURE!
java.lang.AssertionError: 

Expected: is <[zookeeper]>
     but: was <[zookeeper, foo]>
	at org.apache.flink.runtime.highavailability.zookeeper.ZooKeeperHaServicesTest.testSimpleCloseAndCleanupAllData(ZooKeeperHaServicesTest.java:136)