private void verifyProxyCleanup(final String regionName) {
    SystemManagementService service = getSystemManagementService();

    Set<DistributedMember> otherMemberSet = getOtherMembers();
    for (DistributedMember member : otherMemberSet) {
      String alias = "Waiting for the proxy to get deleted at managing node";
      await(alias).untilAsserted(
          () -> assertThat(
              service.getMBeanProxy(service.getRegionMBeanName(member, toPath(regionName)),
                  RegionMXBean.class)).isNull());
    }
  }
Please don't delete verifySystemNotifications. We need to improve verification in this test
class and fix whatever flakiness is in this method.
geode-core/src/distributedTest/java/org/apache/geode/management/RegionManagementDUnitTest.java