More robust MVI test with multiple prop groups

Author: domfournier

tests/run_tests/driver_mvi_test.py

@@ -155,8 +155,12 @@ def test_magnetic_vector_run(
         out_group = run_ws.get_entity("Magnetic Vector Inversion")[0]
         mesh = out_group.get_entity("mesh")[0]
         assert len(mesh.property_groups) == 5
-        assert len(mesh.property_groups[0].properties) == 2
-        assert mesh.property_groups[1].property_group_type == GroupTypeEnum.DIPDIR
+        assert len(mesh.fetch_property_group("Iteration_0").properties) == 2
+        assert len(mesh.fetch_property_group("LP models").properties) == 6
+        assert (
+            mesh.fetch_property_group("Iteration_1").property_group_type
+            == GroupTypeEnum.DIPDIR
+        )
 
 
 def test_magnetic_vector_bounds_run(