Tell template preview to allow international letters

If a service has permission to send international letters then it should
tell template preview, so that template preview knows what rule to
apply when it’s validating the address of the letter.

Depends on:
- [ ] https://github.com/alphagov/notifications-template-preview/pull/445

tests/app/celery/test_letters_pdf_tasks.py

@@ -31,8 +31,10 @@ from app.celery.letters_pdf_tasks import (
 from app.config import QueueNames, TaskNames
 from app.letters.utils import ScanErrorType
 from app.models import (
+    INTERNATIONAL_LETTERS,
     KEY_TYPE_NORMAL,
     KEY_TYPE_TEST,
+    LETTER_TYPE,
     Notification,
     NOTIFICATION_CREATED,
     NOTIFICATION_DELIVERED,
@@ -42,7 +44,7 @@ from app.models import (
     NOTIFICATION_VIRUS_SCAN_FAILED,
 )
 
-from tests.app.db import create_notification, create_letter_branding
+from tests.app.db import create_notification, create_letter_branding, create_service
 
 from tests.conftest import set_config_values
 
@@ -546,16 +548,32 @@ def test_move_invalid_letter_and_update_status_logs_error_and_sets_tech_failure_
     )
 
 
-def test_sanitise_letter_calls_template_preview_sanitise_task(mocker, sample_letter_notification):
+@pytest.mark.parametrize('permissions, expected_international_letters_allowed', (
+    ([LETTER_TYPE], False),
+    ([LETTER_TYPE, INTERNATIONAL_LETTERS], True),
+))
+def test_sanitise_letter_calls_template_preview_sanitise_task(
+    mocker,
+    sample_letter_notification,
+    permissions,
+    expected_international_letters_allowed,
+):
     mock_celery = mocker.patch('app.celery.letters_pdf_tasks.notify_celery.send_task')
     filename = 'NOTIFY.{}'.format(sample_letter_notification.reference)
+    sample_letter_notification.service = create_service(
+        service_permissions=permissions
+    )
     sample_letter_notification.status = NOTIFICATION_PENDING_VIRUS_CHECK
 
     sanitise_letter(filename)
 
     mock_celery.assert_called_once_with(
         name=TaskNames.SANITISE_LETTER,
-        kwargs={'notification_id': str(sample_letter_notification.id), 'filename': filename},
+        kwargs={
+            'notification_id': str(sample_letter_notification.id),
+            'filename': filename,
+            'allow_international_letters': expected_international_letters_allowed,
+        },
         queue=QueueNames.SANITISE_LETTERS,
     )