Infinite loop in tutorial train_dummy_agent.py

[lorepieri8]

num_episodes is never incremented in https://github.com/ColinKohler/BulletArm/blob/main/tutorials/train_dummy_agent.py, resulting in an infinite loop.

Also, I was not able to ever trigger done_idxs = np.nonzero(dones)[0]. Perhaps I did not wait long enough or there are some issues with how done is flagged.