Fix TestTimelineWebServices.testPrimaryFilterNumericString

Running org.apache.hadoop.yarn.server.timeline.webapp.TestTimelineWebServices
Tests run: 28, Failures: 1, Errors: 0, Skipped: 0, Time elapsed: 43.297 sec <<< FAILURE! - in org.apache.hadoop.yarn.server.timeline.webapp.TestTimelineWebServices
testPrimaryFilterNumericString(org.apache.hadoop.yarn.server.timeline.webapp.TestTimelineWebServices)  Time elapsed: 1.209 sec  <<< FAILURE!
java.lang.AssertionError: expected:<0> but was:<3>
	at org.junit.Assert.fail(Assert.java:88)
	at org.junit.Assert.failNotEquals(Assert.java:743)
	at org.junit.Assert.assertEquals(Assert.java:118)
	at org.junit.Assert.assertEquals(Assert.java:555)
	at org.junit.Assert.assertEquals(Assert.java:542)
	at org.apache.hadoop.yarn.server.timeline.webapp.TestTimelineWebServices.testPrimaryFilterNumericString(TestTimelineWebServices.java:348)