Add question about research consent

Since GDPR came into effect it’s less clear about whether we can
contact teams for user research purposes.

If we make people opt-in (or not) we know we’re safe to contact them (or
not).

Since we mostly care about how services are using Notify for real (ie
live services) or services that are considering adopting it (ie those
who have contacted us with a question) it feels like the go-live process
is the most appropriate place to collect this consent.

tests/app/main/views/test_service_settings.py

@@ -728,6 +728,7 @@ def test_should_redirect_after_request_to_go_live(
             'volume_email': '111',
             'volume_sms': '222',
             'volume_letter': '333',
+            'research_consent': 'yes',
         },
         _follow_redirects=True
     )
@@ -743,11 +744,12 @@ def test_should_redirect_after_request_to_go_live(
         'http://localhost/services/{}\n'
         '\n'
         '---\n'
-        'Organisation type: central\n'
+        'Organisation type: Central\n'
         'Agreement signed: Can’t tell (domain is user.gov.uk)\n'
         'Emails in next year: 111\n'
         'Text messages in next year: 222\n'
         'Letters in next year: 333\n'
+        'Consent to research: Yes\n'
         '\n'
         '---\n'
         '{}\tNone\tservice one\tTest User\ttest@user.gov.uk\t-\t21/12/2012\t222\t111\t333'