[v18.x backport] url test
Backport of:
The lib/ changes do not apply, so there's just the test left, but we may still want to land it so we're sure that there's no regression in future backports.
Do not update/delete: Banner broadcast message test data
Do not update/delete: Notification broadcast message test data
Backport of:
The lib/ changes do not apply, so there's just the test left, but we may still want to land it so we're sure that there's no regression in future backports.