Comment 2 for bug 1646596

Adding a task for canonical-devices-system-image for tracking purposes. Having this feature would be the long-term fix for our problem with unity8-session snaps being built with the proposed pocket.

In the meantime, we do have workarounds if needed -- either avoid using the hotfixes silo for building. Or source copy the the packages in that silo to another PPA and then build from there, avoiding bileto.