Fix flake8 errors in utils/test

Author: vrutkovs

.flake8

@@ -1,5 +1,5 @@
 [flake8]
 # TODO: cleanup flake8 issues with utils/test/*
-exclude=.tox,inventory,utils/test
+exclude=.tox,inventory
 max_line_length = 120
 ignore = E501,T003