Flaky-test: ProducerSemaphoreTest.testBatchMessageSendTimeoutProducerSemaphoreRelease

[RobertIndie]

Search before asking

• [X] I searched in the issues and found nothing similar.

Example failure

https://github.com/apache/pulsar/runs/7720536583?check_suite_focus=true#step:10:1299

Exception stacktrace

java.lang.AssertionError: expected [10] but found [9]
  	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:907)
  	at org.testng.Assert.assertEquals(Assert.java:917)
  	at org.apache.pulsar.client.impl.ProducerSemaphoreTest.testBatchMessageSendTimeoutProducerSemaphoreRelease(ProducerSemaphoreTest.java:274)

Are you willing to submit a PR?

• [X] I'm willing to submit a PR!