test_add_distributed_object_listener_object_destroyed

The `test_add_distributed_object_listener_object_destroyed` failed on the PR builder.

It seems that the `DESTROYED` event is not received.

```
16:12:18 ======================================================================
16:12:18 ERROR: test_add_distributed_object_listener_object_destroyed (tests.proxy.distributed_objects_test.DistributedObjectsTest)
16:12:18 ----------------------------------------------------------------------
16:12:18 Traceback (most recent call last):
16:12:18 File "/home/jenkins/jenkins_slave/workspace/python3.7-pr-builder/tests/proxy/distributed_objects_test.py", line 77, in test_add_distributed_object_listener_object_destroyed
16:12:18 self.assertTrueEventually(assert_event)
16:12:18 File "/home/jenkins/jenkins_slave/workspace/python3.7-pr-builder/tests/base.py", line 64, in assertTrueEventually
16:12:18 raise
16:12:18 RuntimeError: No active exception to reraise
```

http://jenkins.hazelcast.com/job/python3.7-pr-builder/183/

Start with test_add_distributed_object_listener_object_destroyed in tests/proxy/distributed_objects_test.py and the assertTrueEventually helper in tests/base.py. Reproduce the failure in the Python 3.7 PR builder and trace why the DESTROYED event is not received. Done means the test reliably receives the event and passes.

Scritto dal modello di indicizzazione a partire dal testo della issue.