code: private Flux<ConfigurationSetting> listSettings(String nextPageLink) {
          Mono<PagedResponse<ConfigurationSetting>> result = service.listKeyValues(serviceEndpoint, nextPageLink);
          return result.flatMapMany(this::extractAndFetchConfigurationSettings);
      }
docs: /*
  Gets all ConfigurationSetting settings given the {@code nextPageLink} that was retrieved from a call to
  {@link ConfigurationAsyncClient#listSettings(SettingSelector)} or a call from this method.
  
  @param nextPageLink The {@link Page#nextPageLink()} from a previous, successful call to one of the list
  operations.
  @return A stream of {@link ConfigurationSetting} from the next page of results.