private DistributedSystemMXBean awaitDistributedSystemMXBean() {
    ManagementService service = getSystemManagementService();

    await().untilAsserted(() -> assertThat(service.getDistributedSystemMXBean()).isNotNull());

    return service.getDistributedSystemMXBean();
  }
Add a Notification listener to DistributedSystemMBean which should gather all the notifications
which are propagated through all individual MemberMBeans Hence Region created/destroyed should
be visible to this listener
geode-core/src/distributedTest/java/org/apache/geode/management/RegionManagementDUnitTest.java