code: public RefreshIndex refreshIndexMethod(String listId, String language) {
          return refreshIndexMethodWithServiceResponseAsync(listId, language).toBlocking().single().body();
      }
docs: Refreshes the index of the list with list Id equal to list ID passed.
  
  @param listId List Id of the image list.
  @param language Language of the terms.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @throws APIErrorException thrown if the request is rejected by server
  @throws RuntimeException all other wrapped checked exceptions if the request fails to be sent
  @return the RefreshIndex object if successful.