docs: public void shutdown() {
          // shutdown each single thread executor in the managed collection
          for (ExecutorService singleThreadExecutorService : singleThreadExecutorServices) {
              shutdownExecutor(singleThreadExecutorService);
          }
  
          // shutdown scheduled executor instance
          shutdownExecutor(getInternalScheduledExecutorService());
          shutdownExecutor(getInternalGpioExecutorService());
  
      }