Update docker sensor test to utilize new BaseSensorTestCase class.
Update docker sensor test to utilize new BaseSensorTestCase class.

tonybaloney/st2contrib,StackStorm/st2contrib,psychopenguin/st2contrib,StackStorm/st2contrib,armab/st2contrib,psychopenguin/st2contrib,pearsontechnology/st2contrib,pearsontechnology/st2contrib,armab/st2contrib,pidah/st2contrib,pidah/st2contrib,pidah/st2contrib,tonybaloney/st2contrib,armab/st2contrib,pearsontechnology/st2contrib,StackStorm/st2contrib,tonybaloney/st2contrib,pearsontechnology/st2contrib