Jersey patients missing URN in national view

[mbarton]

NB: if trying to reproduce this bug with seeded patients you must have #1198 merged, otherwise mainland seeded patients also have a URN

• Create some patients in a mainland trust and then some in Jersey
• Click "View all children" from the dashboard, then "National View"

Expected: Jersey patients show URN, mainland patients show NHS Number
Actual: Jersey patients show ####### in the NHS number column. No URN column is visible.

This issue only affects the national view. The bug depends on whether you navigate to the national view from Jersey, in which case you get the URN column or from a mainland trust when you get NHS number.