code: public ServiceCall<Void> unregisterCallback(UnregisterCallbackOptions unregisterCallbackOptions) {
      Validator.notNull(unregisterCallbackOptions, "unregisterCallbackOptions cannot be null");
      String[] pathSegments = { "v1/unregister_callback" };
      RequestBuilder builder = RequestBuilder.post(RequestBuilder.constructHttpUrl(getEndPoint(), pathSegments));
      Map<String, String> sdkHeaders = SdkCommon.getSdkHeaders("speech_to_text", "v1", "unregisterCallback");
      for (Entry<String, String> header : sdkHeaders.entrySet()) {
        builder.header(header.getKey(), header.getValue());
      }
      builder.query("callback_url", unregisterCallbackOptions.callbackUrl());
      return createServiceCall(builder.build(), ResponseConverterUtils.getVoid());
    }
docs: Unregister a callback.
  
  Unregisters a callback URL that was previously white-listed with a **Register a callback** request for use with the
  asynchronous interface. Once unregistered, the URL can no longer be used with asynchronous recognition requests.
  
  **See also:** [Unregistering a callback
  URL](https://cloud.ibm.com/docs/services/speech-to-text/async.html#unregister).
  
  @param unregisterCallbackOptions the {@link UnregisterCallbackOptions} containing the options for the call
  @return a {@link ServiceCall} with a response type of Void