Add Care Quality Commission to email whitelist

CQC is an executive non-departmental public body, sponsored by the
Department of Health.

They have asked to be allowed to register for Notify using the
`cqc.org.uk` and `digital.cqc.org.uk` domains. We know that this really
is there domain because it’s linked to from here:

https://www.gov.uk/government/organisations/care-quality-commission

tests/app/main/test_validators.py

@@ -90,7 +90,9 @@ def _gen_mock_field(x):
     'test@hmcts.net',
     'test@scotent.co.uk',
     'test@assembly.wales',
-    'test@cjsm.net'
+    'test@cjsm.net',
+    'test@cqc.org.uk',
+    'test@digital.cqc.org.uk',
 ])
 def test_valid_list_of_white_list_email_domains(
     client,