Serialise service, API keys and permissions

By serialising these straight away we can:
- not go back to the database later, potentially closing the connection
  sooner
- potentially cache the serialised data, meaning we don’t touch the
  database at all

tests/app/notifications/test_validators.py

@@ -4,6 +4,7 @@ from flask import current_app
 from notifications_utils import SMS_CHAR_COUNT_LIMIT
 
 import app
+from app.authentication.auth import get_service_model
 from app.dao import templates_dao
 from app.models import SMS_TYPE, EMAIL_TYPE, LETTER_TYPE
 from app.notifications.process_notifications import create_content_for_notification
@@ -439,8 +440,9 @@ def test_rejects_api_calls_with_international_numbers_if_service_does_not_allow_
         notify_db_session,
 ):
     service = create_service(service_permissions=[SMS_TYPE])
+    service_model = get_service_model(service.id)
     with pytest.raises(BadRequestError) as e:
-        validate_and_format_recipient('20-12-1234-1234', key_type, service, SMS_TYPE)
+        validate_and_format_recipient('20-12-1234-1234', key_type, service_model, SMS_TYPE)
     assert e.value.status_code == 400
     assert e.value.message == 'Cannot send to international mobile numbers'
     assert e.value.fields == []
@@ -449,7 +451,8 @@ def test_rejects_api_calls_with_international_numbers_if_service_does_not_allow_
 @pytest.mark.parametrize('key_type', ['test', 'normal'])
 def test_allows_api_calls_with_international_numbers_if_service_does_allow_int_sms(
         key_type, sample_service_full_permissions):
-    result = validate_and_format_recipient('20-12-1234-1234', key_type, sample_service_full_permissions, SMS_TYPE)
+    service_model = get_service_model(sample_service_full_permissions.id)
+    result = validate_and_format_recipient('20-12-1234-1234', key_type, service_model, SMS_TYPE)
     assert result == '201212341234'