getFolder method
Will get a collection of PcoServicesFolder objects (expecting many)
using a path like this: https://api.planningcenteronline.com/services/v2/tag_groups/1/folder
Implementation
Future<PcoCollection<PcoServicesFolder>> getFolder(
{PcoServicesFolderQuery? query}) async {
query ??= PcoServicesFolderQuery();
var url = '$apiEndpoint/folder';
return PcoCollection.fromApiCall<PcoServicesFolder>(url,
query: query, apiVersion: apiVersion);
}