fix items -> updateMany

[mbenyoub]

Hi , thanks for this awesome package, please fix the method updateMany in items module , ( ids are now passed in data )

https://docs.directus.io/reference/items.html#update-multiple-items

Future<DirectusListResponse<T>> updateMany({required List<String> ids, required T data}) async {
    if (ids.isEmpty) return DirectusListResponse.manually([]);
    
    final mapData = converter.toJson({ 'keys': ids, 'data': data,});
    
    return DirectusListResponse.fromRequest(
          () =>
          client.patch(
            '$_endpoint',
            data: mapData,
          ),
      converter: converter,
    );
  }