demandimportpy3: update to pass import checker

hgdemandimport/demandimportpy3.py

@@ -27,11 +27,10 b' This also has some limitations compared '
 from __future__ import absolute_import
 
 import contextlib
-import sys
-
 import importlib.abc
 import importlib.machinery
 import importlib.util
+import sys
 
 _deactivated = False