ISSUE-11032: Flaky-test: ZKSessionTest.testReacquireLeadershipAfterSessionLost

[sijie]

Original Issue: apache#11032

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ZKSessionTest is flaky. The testReacquireLeadershipAfterSessionLost test method fails sporadically.

example failure

Error:  Tests run: 6, Failures: 1, Errors: 0, Skipped: 4, Time elapsed: 31.46 s <<< FAILURE! - in org.apache.pulsar.metadata.ZKSessionTest
Error:  testReacquireLeadershipAfterSessionLost(org.apache.pulsar.metadata.ZKSessionTest)  Time elapsed: 15.396 s  <<< FAILURE!
org.awaitility.core.ConditionTimeoutException: Assertion condition defined as a lambda expression in org.apache.pulsar.metadata.ZKSessionTest that uses org.apache.pulsar.metadata.api.coordination.LeaderElection expected [Leading] but found [NoLeader] within 10 seconds.
	at org.awaitility.core.ConditionAwaiter.await(ConditionAwaiter.java:165)
	at org.awaitility.core.AssertionCondition.await(AssertionCondition.java:119)
	at org.awaitility.core.AssertionCondition.await(AssertionCondition.java:31)
	at org.awaitility.core.ConditionFactory.until(ConditionFactory.java:895)
	at org.awaitility.core.ConditionFactory.untilAsserted(ConditionFactory.java:679)
	at org.apache.pulsar.metadata.ZKSessionTest.testReacquireLeadershipAfterSessionLost(ZKSessionTest.java:174)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.base/java.lang.reflect.Method.invoke(Method.java:566)
	at org.testng.internal.MethodInvocationHelper.invokeMethod(MethodInvocationHelper.java:132)
	at org.testng.internal.InvokeMethodRunnable.runOne(InvokeMethodRunnable.java:45)
	at org.testng.internal.InvokeMethodRunnable.call(InvokeMethodRunnable.java:73)
	at org.testng.internal.InvokeMethodRunnable.call(InvokeMethodRunnable.java:11)
	at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
	at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)
	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)
	at java.base/java.lang.Thread.run(Thread.java:829)
Caused by: java.lang.AssertionError: expected [Leading] but found [NoLeader]
	at org.testng.Assert.fail(Assert.java:99)
	at org.testng.Assert.failNotEquals(Assert.java:1037)
	at org.testng.Assert.assertEqualsImpl(Assert.java:140)
	at org.testng.Assert.assertEquals(Assert.java:122)
	at org.testng.Assert.assertEquals(Assert.java:617)
	at org.apache.pulsar.metadata.ZKSessionTest.lambda$testReacquireLeadershipAfterSessionLost$1(ZKSessionTest.java:175)
	at org.awaitility.core.AssertionCondition.lambda$new$0(AssertionCondition.java:53)
	at org.awaitility.core.ConditionAwaiter$ConditionPoller.call(ConditionAwaiter.java:222)
	at org.awaitility.core.ConditionAwaiter$ConditionPoller.call(ConditionAwaiter.java:209)
	... 4 more