[dex] hab service runs but returns 404 error

[gavindidrichsen]

This is a placeholder for the issue in core-plans here habitat-sh/core-plans#3451

In summary, core/dex is a habitat service and exports port 5556. After starting a hab studio with HAB_DOCKER_OPTS="-p 5556:5556" hab studio enter -D and loading the dex service, then the following is observed:

➜  DUMP curl http://localhost:5556/
404 page not found

It's not clear whether dex is working or not.