corrected fabfile flake8 error

circle/fabfile.py

@@ -92,8 +92,9 @@ def selenium(test=""):
     "Run portal selenium tests"
     with _workon("circle"), cd("~/circle/circle"):
         # TODO Check if the user have any X so we don't have force xvfb
-        run("xvfb-run ./manage.py test --settings=circle.settings.selenium_test"
-            "%s" % test)
+        run("xvfb-run ./manage.py test "
+            "--settings=circle.settings.selenium_test %(test)s" % {
+                'test': test})
 
 
 def pull(dir="~/circle/circle"):