Fix flake8 errors in doc config

Author: tleonhardt

docs/conf.py

@@ -17,9 +17,6 @@
 add these directories to sys.path here. If the directory is relative to the
 documentation root, use os.path.abspath to make it absolute, like shown here.
 """
-import os
-import sys
-
 from pkg_resources import get_distribution
 
 # Import for custom theme from Read the Docs