getItems method

Will get a collection of PcoServicesItem objects (expecting many) using a path like this: https://api.planningcenteronline.com/services/v2/series/1/plans/1/live/1/items

Implementation

Future<PcoCollection<PcoServicesItem>> getItems(
    {PcoServicesItemQuery? query}) async {
  query ??= PcoServicesItemQuery();
  var url = '$apiEndpoint/items';
  return PcoCollection.fromApiCall<PcoServicesItem>(url,
      query: query, apiVersion: apiVersion);
}