[scripts] remove old py2 compat imports

src/pymor/scripts/pymor_demo.py

@@ -3,7 +3,6 @@
 # Copyright pyMOR developers and contributors. All rights reserved.
 # License: BSD 2-Clause License (https://opensource.org/licenses/BSD-2-Clause)
 
-from __future__ import absolute_import, division, print_function
 
 import importlib
 import pkgutil