Deleting a trunk deletes the incorrect records from the outbound_route_trunks table

When a trunk is deleted, the incorrect record is deleted from the outbound_route_trunks table.

Steps to replicate

1) Create two trunks, they will have and id of 1 and 2 in the trunks table.
2) Create two outbound routes, they will have an id of 1 and 2 in the outbound_routes table.
3) Associate trunk 1 to outbound route 2 and trunk 2 to outbound route 1.
4) Delete trunk 1. You will see that trunk 2 will be removed from outbound route 1.