Processes in docker containers should not run as root, as it presents a security risk.

See https://medium.com/@mccode/processes-in-containers-should-not-run-as-root-2feae3f0df3b for more information.

• Modify the docker build scripts to generate the docker image so that Monkey Island is not running as root (0d). @mssalvatore
• Check whether or not the mongodb:4.2 image runs as root. If it does, adjust our instructions in the documentation hub to run as a regular user (0d). @mssalvatore
• Run blackbox tests (0d). @mssalvatore