The shared volume will be used by each container
to share their specific traefik dynamic
configuration to allow Traefik to dynamically
configure the backend.
Here we rename the containers stack to the docker stack.
The docker_network stack is now deleted and the docker network is
now managed in the docker stack.
This commit adds the new containers stack which
now builds the traefik docker image and creates
the traefik docker container.
Pulumi needed to be downgraded to version 3.2.1
because later versions panic when building
the docker image.
