Update sample_service_full_perms to leave out letters_as_pdf permissions

- as letters_as_pdf is a temporary service permission until the build dvla file process is deprecated rather than update all the tests to remove the permission so that they pass, lets remove it here instead

tests/app/conftest.py

@@ -161,7 +161,7 @@ def sample_service(
         'message_limit': limit,
         'restricted': restricted,
         'email_from': email_from,
-        'created_by': user
+        'created_by': user,
     }
     service = Service.query.filter_by(name=service_name).first()
     if not service:
@@ -188,7 +188,7 @@ def sample_service_full_permissions(notify_db, notify_db_session):
         notify_db_session,
         # ensure name doesn't clash with regular sample service
         service_name="sample service full permissions",
-        permissions=SERVICE_PERMISSION_TYPES
+        permissions=set(SERVICE_PERMISSION_TYPES) - {'letters_as_pdf'}
     )
 
 
@@ -299,10 +299,6 @@ def sample_template_without_email_permission(notify_db, notify_db_session):
 
 @pytest.fixture
 def sample_letter_template(sample_service_full_permissions):
-    # remove letters_as_pdf from fixture until we drop building of dvla files
-    from app.dao.service_permissions_dao import dao_remove_service_permission
-    dao_remove_service_permission(sample_service_full_permissions.id, 'letters_as_pdf')
-
     return create_template(sample_service_full_permissions, template_type=LETTER_TYPE)