Put environment URL in feedback tickets

So that:
- we know what environment a request has been sent from

app/main/views/feedback.py

@@ -16,10 +16,12 @@ def feedback():
             'person_email': current_app.config.get('DESKPRO_PERSON_EMAIL'),
             'department_id': current_app.config.get('DESKPRO_TEAM_ID'),
             'subject': 'Notify feedback',
-            'message': '{}\n{}\n{}'.format(
+            'message': 'Environment: {}\n\n{}\n{}\n{}'.format(
+                url_for('main.index', _external=True),
                 form.name.data,
                 form.email_address.data,
-                form.feedback.data)
+                form.feedback.data
+            )
         }
         headers = {
             "X-DeskPRO-API-Key": current_app.config.get('DESKPRO_API_KEY'),

tests/app/main/views/test_feedback.py

@@ -49,7 +49,7 @@ def test_post_feedback_with_no_name_email(app_, mocker):
                 data={
                     'department_id': ANY,
                     'subject': 'Notify feedback',
-                    'message': '\n\nblah',
+                    'message': 'Environment: http://localhost/\n\n\n\nblah',
                     'person_email': ANY},
                 headers=ANY)
 
@@ -69,7 +69,7 @@ def test_post_feedback_with_name_email(app_, mocker):
                 data={
                     'subject': 'Notify feedback',
                     'department_id': ANY,
-                    'message': 'Steve Irwin\nrip@gmail.com\nblah',
+                    'message': 'Environment: http://localhost/\n\nSteve Irwin\nrip@gmail.com\nblah',
                     'person_email': ANY},
                 headers=ANY)
 
@@ -94,7 +94,7 @@ def test_log_error_on_post(app_, mocker):
                 data={
                     'subject': 'Notify feedback',
                     'department_id': ANY,
-                    'message': 'Steve Irwin\nrip@gmail.com\nblah',
+                    'message': 'Environment: http://localhost/\n\nSteve Irwin\nrip@gmail.com\nblah',
                     'person_email': ANY},
                 headers=ANY)
             mock_logger.assert_called_with(