Agreement edit/new: When "Linked agreement's relationship to the agreement being edited" is left blank, give it focus

Description

When a "Related agreement" is added to an agreement the field "Linked agreement's relationship to the agreement being edited" is mandatory. When the agreement is saved, if the field is left blank, focus should shift to the field so that a user using keyboard-only can complete the field.

Actual behaviour

If the field "Linked agreement's relationship to the agreement being edited" is left blank, when the agreement is saved. focus is not given to the field.

Steps to recreate

1. Edit an agreement
2. Open the "Related agreements accordion"
3. Select "Add related agreement"
4. Use the "Link agreement" button and select an agreement using the lookup modal
5. Select "Save & close". A validation message is displayed for the field "Linked agreement's relationship to the agreement being edited" but the field is not given focus.