@Override
    public synchronized void memberJoined(ClientMembershipEvent event) {
      joins++;
      System.out.println("memberJoined invoked");
      notifyAll();
    }
Assert that there is one endpoint with the given host in port on the client vm.

@param vm - the vm the client is running in
@param expectedPorts - The server ports we expect the client to be connected to.
geode-core/src/distributedTest/java/org/apache/geode/cache/client/internal/AutoConnectionSourceDUnitTest.java