Remove domain columns from branding table

This relationship is via the `Organisation` now; we don’t use this
column to fudge a relationship based on the user’s email address and the
matching something in these columns.

app/service/rest.py

@@ -27,7 +27,6 @@ from app.dao.fact_notification_status_dao import (
     fetch_stats_for_all_services_by_date_range, fetch_monthly_template_usage_for_service
 )
 from app.dao.inbound_numbers_dao import dao_allocate_number_for_service
-from app.dao.letter_branding_dao import dao_get_letter_branding_by_domain
 from app.dao.organisation_dao import dao_get_organisation_by_service_id
 from app.dao.service_data_retention_dao import (
     fetch_service_data_retention,
@@ -186,7 +185,8 @@ def create_service():
     if not data.get('user_id'):
         errors = {'user_id': ['Missing data for required field.']}
         raise InvalidRequest(errors, status_code=400)
-    domain = data.pop('service_domain', None)
+    data.pop('service_domain', None)
+
     # validate json with marshmallow
     service_schema.load(data)
 
@@ -195,8 +195,7 @@ def create_service():
     # unpack valid json into service object
     valid_service = Service.from_json(data)
 
-    letter_branding = dao_get_letter_branding_by_domain(domain)
-    dao_create_service(valid_service, user, letter_branding=letter_branding)
+    dao_create_service(valid_service, user)
 
     return jsonify(data=service_schema.dump(valid_service).data), 201