cli: hack: sous build: grab repo from RFF
cli: hack: sous build: grab repo from RFF

- This gets tests passing but needs refactoring.
- Specifically, the GetArtifact action should not
  depend on flags, but take same context as other
  commands, probably via RFF.
- May be better to define SourceID context as a top-
  level thing rather than use RFF, which is over-broad.

opentable/sous,opentable/sous,samsalisbury/sous,opentable/sous,samsalisbury/sous,opentable/sous,samsalisbury/sous,samsalisbury/sous,samsalisbury/sous,opentable/sous