[fix][flaky-test] Fix flaky test testBacklogNoDelayedForPartitionedTopic

[gaozhangmin]

Motivation

Fix flaky test testBacklogNoDelayedForPartitionedTopic

Error:  testBacklogNoDelayedForPartitionedTopic(org.apache.pulsar.broker.admin.AdminApi2Test)  Time elapsed: 2.24 s  <<< FAILURE!
  java.lang.AssertionError: expected [5] but found [6]
  	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:797)
  	at org.testng.Assert.assertEquals(Assert.java:807)
  	at org.apache.pulsar.broker.admin.AdminApi2Test.testBacklogNoDelayedForPartitionedTopic(AdminApi2Test.java:1627)
  	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
  	at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
  	at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
  	at java.base/java.lang.reflect.Method.invoke(Method.java:568)
  	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:1136)
  	at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:635)
  	at java.base/java.lang.Thread.run(Thread.java:833)

Modifications

Message is not added to delayed priorityQueue immediately after send.

Documentation

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[gaozhangmin]

/pulsarbot run-failure-checks