Add a flash message to confirm sending has started

app/main/views/sms.py

@@ -115,6 +115,7 @@ def check_sms(service_id, upload_id):
             else:
                 raise e
 
+        flash('We’ve started sending your messages', 'default_with_tick')
         return redirect(url_for('main.view_job',
                         service_id=service_id,
                         job_id=upload_id))

tests/app/main/views/test_sms.py

@@ -126,4 +126,5 @@ def test_create_job_should_call_api(app_,
             response = client.post(url, data=job_data, follow_redirects=True)
 
         assert response.status_code == 200
+        assert 'We’ve started sending your messages' in response.get_data(as_text=True)
         mock_create_job.assert_called_with(job_id, service_id, template_id, original_file_name)