Delete caches when user accepts invite

Accepting an invite changes:
- the `user_to_service` list of users returned by `GET /service/<id>`
- the `services` list return by `GET /user/<id>`

The latter change is causing the functional tests to fail.

app/notify_client/invite_api_client.py

@@ -1,4 +1,4 @@
-from app.notify_client import NotifyAdminAPIClient, _attach_current_user
+from app.notify_client import NotifyAdminAPIClient, _attach_current_user, cache
 from app.notify_client.models import (
     InvitedUser,
     translate_permissions_from_admin_roles_to_db,
@@ -44,6 +44,8 @@ class InviteApiClient(NotifyAdminAPIClient):
         self.post(url='/service/{0}/invite/{1}'.format(service_id, invited_user_id),
                   data=data)
 
+    @cache.delete('service')
+    @cache.delete('user', key_from_args=[1])
     def accept_invite(self, service_id, invited_user_id):
         data = {'status': 'accepted'}
         self.post(url='/service/{0}/invite/{1}'.format(service_id, invited_user_id),

tests/app/notify_client/test_service_api_client.py

@@ -3,7 +3,7 @@ from unittest.mock import call
 import pytest
 from tests.conftest import SERVICE_ONE_ID, fake_uuid
 
-from app import service_api_client, user_api_client
+from app import invite_api_client, service_api_client, user_api_client
 from app.notify_client.service_api_client import ServiceAPIClient
 
 
@@ -221,6 +221,7 @@ def test_returns_value_from_cache(
     (service_api_client, 'update_service_callback_api', [SERVICE_ONE_ID] + [''] * 4, {}),
     (service_api_client, 'create_service_callback_api', [SERVICE_ONE_ID] + [''] * 3, {}),
     (user_api_client, 'add_user_to_service', [SERVICE_ONE_ID, fake_uuid(), []], {}),
+    (invite_api_client, 'accept_invite', [SERVICE_ONE_ID, fake_uuid()], {}),
 ])
 def test_deletes_service_cache(
     app_,

tests/app/notify_client/test_user_client.py

@@ -3,7 +3,7 @@ from unittest.mock import call
 import pytest
 from tests.conftest import SERVICE_ONE_ID, api_user_pending, fake_uuid
 
-from app import service_api_client, user_api_client
+from app import invite_api_client, service_api_client, user_api_client
 from app.notify_client.models import User
 
 user_id = fake_uuid()
@@ -248,6 +248,7 @@ def test_returns_value_from_cache(
     (user_api_client, 'set_user_permissions', [user_id, SERVICE_ONE_ID, []], {}),
     (user_api_client, 'activate_user', [api_user_pending(fake_uuid())], {}),
     (service_api_client, 'remove_user_from_service', [SERVICE_ONE_ID, user_id], {}),
+    (invite_api_client, 'accept_invite', [SERVICE_ONE_ID, user_id], {}),
 ])
 def test_deletes_user_cache(
     app_,