Continuous CartPole Robot-Supervisor - fix coordinate system

[KelvinYang0320]

Check if it works correctly without training:

1. Download the pretrained agent into the following folder: deepworlds/examples/cartpole/cartpole_continuous/controllers/robot_supervisor_manager/models/saved/default_ddpg

Directories structure:

\robot_supervisor_manager
  \agent
    \...
  \model
    \saved
      \default_ddpg
        \Actor_ddpg
        \Critic_ddpg
        \TargetActor_ddpg
        \TargetCritic_ddpg
  \...

2. Add agent.load('./PPO') to controllers/robot_supervisor_manager/DDPG_runner.py

   agent = DDPGAgent(...)
   agent.load_models()

3. You should be able to see that the agent works correctly.

https://user-images.githubusercontent.com/49781698/175893059-e27fb65f-c321-4175-91be-e6f063ee797b.mp4