TST: Check container error code

unittests/test_error_handling.py

@@ -272,6 +272,7 @@ def test_container_with_faulty_elements():
         raise_errors(cont)
     te = e.value
     assert te.get_container() == cont
+    assert te.get_code() == container_code
     # no healthy entity caused an error
     for good in [good_rec, good_prop]:
         assert not good in te.all_entities