code: public void finish() throws Exception {
          assertTrue(format("Did you call finish() from outside @%s test?", Specification.class.getSimpleName()),
                  !latch.isInInitState());
  
          // wait for script to finish
          latch.notifyStartable();
  
          latch.awaitFinished();
      }
docs: Blocking call to await for the K3po threads to stop executing.  If the connects have not already been initiated via the
  start() method, they will be implicitly called.
  @throws Exception if an error has occurred in the execution of the tests.