Description of PR

I saw the test TestAbstractYarnScheduler.testGetRunningContainersToKill[FAIR] fails occasionally

Error:  org.apache.hadoop.yarn.server.resourcemanager.scheduler.TestAbstractYarnScheduler.testGetRunningContainersToKill[FAIR] -- Time elapsed: 0.016 s <<< FAILURE!
java.lang.AssertionError: expected:<[OPPORTUNISTIC1, OPPORTUNISTIC0, GUARANTEED1, GUARANTEED0, AM1, AM0]> but was:<[OPPORTUNISTIC0, OPPORTUNISTIC1, GUARANTEED1, GUARANTEED0, AM1, AM0]>
	at org.junit.Assert.fail(Assert.java:89)
	at org.junit.Assert.failNotEquals(Assert.java:835)
	at org.junit.Assert.assertEquals(Assert.java:120)
	at org.junit.Assert.assertEquals(Assert.java:146)
	at org.apache.hadoop.yarn.server.resourcemanager.scheduler.TestAbstractYarnScheduler.testGetRunningContainersToKill(TestAbstractYarnScheduler.java:1583)
...

this is likely due to the two System.currentTimeMillis() return same value.

Returns the current time in milliseconds. Note that while the unit of time of the return value is a millisecond, the granularity of the value depends on the underlying operating system and may be larger. For example, many operating systems measure time in units of tens of milliseconds.

How was this patch tested?

Run the modified test locally multi times.

For code changes:

• Does the title or this PR starts with the corresponding JIRA issue id (e.g. 'HADOOP-17799. Your PR title ...')?
• Object storage: have the integration tests been executed and the endpoint declared according to the connector-specific documentation?
• If adding new dependencies to the code, are these dependencies licensed in a way that is compatible for inclusion under ASF 2.0?
• If applicable, have you updated the LICENSE, LICENSE-binary, NOTICE-binary files?