Remove pentesters from list of domains

Reverts https://github.com/alphagov/notifications-admin/pull/1071

app/config.py

@@ -76,7 +76,6 @@ class Config(object):
         r"ucds\.email",
         r"naturalengland\.org\.uk",
         r"hmcts\.net",
-        r"irmsecurity\.com",  # temp addition for pen testers to be able to create account
     ]
 
 

tests/app/main/test_validators.py

@@ -82,7 +82,6 @@ def _gen_mock_field(x):
     'test@ucds.email',
     'test@naturalengland.org.uk',
     'test@hmcts.net',
-    'test@irmsecurity.com'  # remove once pen test complete
 ])
 def test_valid_list_of_white_list_email_domains(app_, email):
     with app_.test_request_context():