code: public Map<String, String> listEndpoints(UUID appId) {
          return listEndpointsWithServiceResponseAsync(appId).toBlocking().single().body();
      }
docs: Returns the available endpoint deployment regions and URLs.
  
  @param appId The application ID.
  @throws IllegalArgumentException thrown if parameters fail the validation
  @throws ErrorResponseException thrown if the request is rejected by server
  @throws RuntimeException all other wrapped checked exceptions if the request fails to be sent
  @return the Map&lt;String, String&gt; object if successful.