Use Coach 0.11 for Object Tracker sample (aws#665)

Author: x77a1

reinforcement_learning/rl_objecttracker_robomaker_coach_gazebo/rl_objecttracker_coach_robomaker.ipynb

@@ -375,7 +375,7 @@
  " source_dir='src',\n",
  " dependencies=[\"common/sagemaker_rl\"],\n",
  " toolkit=RLToolkit.COACH,\n",
- " toolkit_version='0.11.1',\n",
+ " toolkit_version='0.11',\n",
  " framework=RLFramework.TENSORFLOW,\n",
  " role=role,\n",
  " train_instance_type=instance_type,\n",