Geo node primary checkbox should be below the geo node URL field

The geo node field should be below the URL so that it is apparent that the checkbox is related to the URL. Putting the checkbox above makes this unclear.

This screen is found at https://gitlab.example.com/admin/geo_nodes

Reported during geo live stream: https://docs.google.com/document/d/1-93kEWlL5npXcrgS1moEkzSwkUODVLpN4C6KC_S7YFM/edit