Fix lesson event graphene type

aleksis/apps/chronos/schema/__init__.py

@@ -84,7 +84,7 @@ class LessonEventType(DjangoObjectType):
         if not str(root.pk).startswith("DUMMY") and hasattr(root, "groups"):
             return root.groups
         elif root.amends:
-            root.amends.groups
+            return root.amends.groups
         return []
 
     @staticmethod
@@ -92,7 +92,7 @@ class LessonEventType(DjangoObjectType):
         if not str(root.pk).startswith("DUMMY") and hasattr(root, "rooms"):
             return root.rooms
         elif root.amends:
-            root.amends.rooms
+            return root.amends.rooms
         return []