Limit big numbers to the last 7 days

Implements and depends on:
- https://github.com/alphagov/notifications-api/pull/241

tests/app/main/views/test_dashboard.py

@@ -77,7 +77,7 @@ def test_should_show_recent_templates_on_dashboard(app_,
 
         assert response.status_code == 200
         response.get_data(as_text=True)
-        mock_get_service_statistics.assert_called_once_with(SERVICE_ONE_ID)
+        mock_get_service_statistics.assert_called_once_with(SERVICE_ONE_ID, limit_days=7)
         mock_template_stats.assert_called_once_with(SERVICE_ONE_ID)
 
         page = BeautifulSoup(response.data.decode('utf-8'), 'html.parser')

tests/conftest.py

@@ -172,7 +172,7 @@ def mock_delete_service(mocker, mock_get_service):
 
 @pytest.fixture(scope='function')
 def mock_get_service_statistics(mocker):
-    def _create(service_id):
+    def _create(service_id, limit_days=None):
         return {'data': [{}]}
 
     return mocker.patch(