pep8 blank lines fixes

flake8 --select W391,E302,E301,E304

autopep8 can't fix W391 even though it claims it can.
Fixed using a simple custom script.

modules/sueurdemetal/test.py

@@ -22,6 +22,7 @@ from weboob.tools.test import BackendTest
 from weboob.capabilities.calendar import Query, CATEGORIES
 from datetime import datetime, timedelta
 
+
 class SueurDeMetalTest(BackendTest):
     MODULE = 'sueurdemetal'