This replaces the failing `docker rmi $(docker image ls -aq)` command with the more flexible and versatile `docker image prune -a -f` command.
The `docker image prune -a -f` command will prune images from previous runs if they are present, and will do nothing if there are no old images present. This accomplishes the same thing that the ` docker rmi $(docker image ls -aq)` was trying to accomplish (but was failing when there were no previous/old images to find/delete)
