Fix our failing test suite (#13)

* Edit file name to be specific to our use case

* Rename single test

Author: willGraham01

tests/test_group_layer_widget.py

@@ -0,0 +1,7 @@
+from napari_experimental._widget import GroupLayerWidget
+from qtpy.QtWidgets import QWidget
+
+
+def test_widget_creation(make_napari_viewer_proxy) -> None:
+    viewer = make_napari_viewer_proxy()
+    assert isinstance(GroupLayerWidget(viewer), QWidget)