Write security review for Geo into Geo documentation
As a follow-up to https://gitlab.com/gitlab-org/gitlab-ee/issues/3865:
Take the information from https://docs.google.com/document/d/1WiTyWtkeymoJc5JZBJ4qPeFo8ZvAWc3dT3GBIzqjqGA/edit?ts=59f36bd1# and place it in the documentation for geo itself.
@axil @marcia is there precedent for this how/where to discuss security questions of a feature set? (We have https://about.gitlab.com/security/ )