Previously every deployment (even just for a single tag, such as
`ansible-playbook site.yml --tags landingpage`) would have the caddy
deployment in its dependency.
That meant in effect whenever there was an updated caddy image, the role
would update it and we would lose all previous caddy configuration -
which in turn would necessitate a complete redeploymnet of all steps.
This is now not the case anymore.
If a domain has been declared for the host, the upstream file will proxy
at a subdomain named for the stack it proxies to,
otherwise it will do the same for the path.
