Add level to expire session test

Author: uralbash

sqlalchemy_mptt/tests/tree_testing_base.py

@@ -1740,7 +1740,11 @@ def test_session_expire_for_move_after_to_new_tree(self):
         self.assertEqual(node.tree_id, 2)
         self.assertEqual(node.level, 1)
         self.assertEqual(node.parent_id, None)
+
         self.assertEqual(children[0].tree_id, 2)
-        self.assertEqual(children[1].tree_id, 2)
         self.assertEqual(children[0].parent_id, 4)
+        self.assertEqual(children[0].level, 2)
+
+        self.assertEqual(children[1].tree_id, 2)
         self.assertEqual(children[1].parent_id, 4)
+        self.assertEqual(children[1].level, 2)