Train DreamerV3 agent:
bash run/navigation5x5.sh

Train DreamerV3:pretrained agent:
1) Assume that DreamerV3 checkpoint is in dreamerv3/dreamerv3-jax_navigation5x5/run_monolithic_0
2) cp dreamerv3/dreamerv3-jax_navigation5x5/run_monolithic_0 dreamerv3/dreamerv3-jax_navigation5x5/run_monolithic-pretrain_0
3) bash run/navigation5x5_pretrained.sh
