Self-check allows workstation to be set to sys

[Terran McCanna]

The process of setting up a workstation for the self-check interface allows staff to choose a system or even the consortium for the workstation instead of restricting it to branches only like the staff client does.

When this happens, it causes problems with printing receipts because it doesn't pull data from the correct branch hours, it can cause problems with circulation rules, and it can cause problems with reporting / statistics.