docs: public Flux<ConfigurationSetting> listSettings(SettingSelector options) {
          Mono<PagedResponse<ConfigurationSetting>> result;
          if (options != null) {
              String fields = getSelectQuery(options.fields());
              result = service.listKeyValues(serviceEndpoint, options.key(), options.label(), fields, options.acceptDateTime());
          } else {
              result = service.listKeyValues(serviceEndpoint, null, null, null, null);
          }
  
          return result.flatMapMany(this::extractAndFetchConfigurationSettings);
      }