Flaky tests in TestContainerReuse due to race condition in DelayedContainerManager thread

Couple of TestContainerReuse tests are failing due to minor race condition in DelayedContainerManager thread.

Wanted but not invoked:
taskSchedulerEventHandlerForTest.taskAllocated(
Mock for TaskAttempt, hashCode: 290467934,
<any>,
Container: [ContainerId: container_1_0001_01_000001, NodeId: host1:0, NodeHttpAddress: host1:0, Resource: <memory:1024, vCores:1>, Priority: 1, Token: null, ]
);
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:580)

However, there were other interactions with this mock:
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:531)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:531)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:531)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:532)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:532)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:532)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:532)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:534)
-> at org.apache.tez.dag.app.rm.TaskSchedulerAppCallbackWrapper$SetApplicationRegistrationDataCallable.call(TaskSchedulerAppCallbackWrapper.java:244)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:570)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseWithTaskSpecificLaunchCmdOption(TestContainerReuse.java:571)

Wanted but not invoked:
taskSchedulerEventHandlerForTest.taskAllocated(
Mock for TaskAttempt, hashCode: 392638651,
<any>,
Container: [ContainerId: container_1_0001_01_000001, NodeId: host1:0, NodeHttpAddress: host1:0, Resource: <memory:1024, vCores:1>, Priority: 5, Token: null, ]
);
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:333)

However, there were other interactions with this mock:
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:289)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:289)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:289)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:290)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:290)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:290)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:290)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:292)
-> at org.apache.tez.dag.app.rm.TaskSchedulerAppCallbackWrapper$SetApplicationRegistrationDataCallable.call(TaskSchedulerAppCallbackWrapper.java:244)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:323)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:324)

at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerNotAvailable(TestContainerReuse.java:333)

org.mockito.exceptions.verification.WantedButNotInvoked:
Wanted but not invoked:
taskSchedulerEventHandlerForTest.taskAllocated(
Mock for TaskAttempt, hashCode: 1830222901,
<any>,
Container: [ContainerId: container_1_0001_01_000001, NodeId: host1:0, NodeHttpAddress: host1:0, Resource: <memory:1024, vCores:1>, Priority: 3, Token: null, ]
);
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:909)

However, there were other interactions with this mock:
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:861)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:861)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:861)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:862)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:862)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:862)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:862)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:864)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:900)
-> at org.apache.tez.dag.app.rm.TaskSchedulerAppCallbackWrapper$SetApplicationRegistrationDataCallable.call(TaskSchedulerAppCallbackWrapper.java:244)

at org.apache.tez.dag.app.rm.TestContainerReuse.testReuseAcrossVertices(TestContainerReuse.java:909)

testDelayedReuseContainerBecomesAvailable(org.apache.tez.dag.app.rm.TestContainerReuse) Time elapsed: 0.053 sec <<< FAILURE!
org.mockito.exceptions.verification.WantedButNotInvoked:
Wanted but not invoked:
taskSchedulerEventHandlerForTest.taskAllocated(
Mock for TaskAttempt, hashCode: 1829491577,
<any>,
Container: [ContainerId: container_1_0001_01_000001, NodeId: host1:0, NodeHttpAddress: host1:0, Resource: <memory:1024, vCores:1>, Priority: 5, Token: null, ]
);
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:202)

However, there were other interactions with this mock:
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:151)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:151)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:151)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:152)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:152)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:152)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:152)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:154)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:191)
-> at org.apache.tez.dag.app.rm.TestContainerReuse.testDelayedReuseContainerBecomesAvailable(TestContainerReuse.java:192)
-> at org.apache.tez.dag.app.rm.TaskSchedulerAppCallbackWrapper$SetApplicationRegistrationDataCallable.call(TaskSchedulerAppCallbackWrapper.java:244)