test_sphinx: cosmetic change

Change-Id: Ifb1fa97c42d44422829e32bb6d27806e7a84f67e
Reviewed-on: http://gerrit.aldebaran.lan/33585
Reviewed-by: dmerejkowsky <dmerejkowsky@aldebaran-robotics.com>
Tested-by: dmerejkowsky <dmerejkowsky@aldebaran-robotics.com>