docs: public void unsubscribe(Installation installation, String categoryToUnsubscribe) {
  
          String url = "";
          try {
              url = IID_URL + installation.getDeviceToken() + "/rel/topics/" + URLEncoder.encode(categoryToUnsubscribe, StandardCharsets.UTF_8.toString());
          } catch (UnsupportedEncodingException e1) {
              //
          }
  
          try {
              delete(url);
          } catch (IOException e) {
              logger.debug("Unregistering device from topic was unsuccessfull");
          }
      }