Use Github workflow to update p4lang/behavioral-model Docker image (#1027)
Use Github workflow to update p4lang/behavioral-model Docker image (#1027)

Now that Docker has disabled automatic builds for free accounts, we need to find
a different solution.
This is temporary: ideally I'd like to migrate everything from Travis to Github
workflows. The Docker image should also be updated every time the base image
(p4lang/pi) is updated, not just for push events.
p4lang/behavioral-model,p4lang/behavioral-model,p4lang/behavioral-model,p4lang/behavioral-model,p4lang/behavioral-model