Update dockerfile to current on dockerhub

[camfairchild]

This dockerfile reflects the current docker image for opentensorfdn/bittensor on dockerhub.

The current image and tag is opentensorfdn/bittensor:3.3.3-torch1.12.0-cuda11.3-pm2

This image contains pm2 htop tmux curl along with the bittensor dependencies.

This PR also adds netcat to the image as I think it's useful.