code: public Observable<Void> publishEventsAsync(String topicHostname, List<EventGridEvent> events) {
          return publishEventsWithServiceResponseAsync(topicHostname, events).map(new Func1<ServiceResponse<Void>, Void>() {
              @Override
              public Void call(ServiceResponse<Void> response) {
                  return response.body();
              }
          });
      }
docs: Publishes a batch of events to an Azure Event Grid topic.
  
  @param topicHostname The host name of the topic, e.g. topic1.westus2-1.eventgrid.azure.net
  @param events An array of events to be published to Event Grid.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @return the {@link ServiceResponse} object if successful.