AdaptiveSchedulerTest.testRequirementLowerBoundDecreaseAfterResourceScarcityBelowAvailableSlots times out

Jan 30 03:15:46 "ForkJoinPool-420-worker-25" #9746 daemon prio=5 os_prio=0 tid=0x00007fdfbb635800 nid=0x2dbd waiting on condition [0x00007fdf39528000]
Jan 30 03:15:46    java.lang.Thread.State: WAITING (parking)
Jan 30 03:15:46 	at sun.misc.Unsafe.park(Native Method)
Jan 30 03:15:46 	- parking to wait for  <0x00000000fe642548> (a java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject)
Jan 30 03:15:46 	at java.util.concurrent.locks.LockSupport.park(LockSupport.java:175)
Jan 30 03:15:46 	at java.util.concurrent.locks.AbstractQueuedSynchronizer$ConditionObject.await(AbstractQueuedSynchronizer.java:2039)
Jan 30 03:15:46 	at java.util.concurrent.ArrayBlockingQueue.take(ArrayBlockingQueue.java:403)
Jan 30 03:15:46 	at org.apache.flink.runtime.scheduler.adaptive.AdaptiveSchedulerTest$SubmissionBufferingTaskManagerGateway.waitForSubmissions(AdaptiveSchedulerTest.java:2225)
Jan 30 03:15:46 	at org.apache.flink.runtime.scheduler.adaptive.AdaptiveSchedulerTest.awaitJobReachingParallelism(AdaptiveSchedulerTest.java:1333)
Jan 30 03:15:46 	at org.apache.flink.runtime.scheduler.adaptive.AdaptiveSchedulerTest.testRequirementLowerBoundDecreaseAfterResourceScarcityBelowAvailableSlots(AdaptiveSchedulerTest.java:1273)
Jan 30 03:15:46 	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
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