Fix email test

The Mailer expects the config object to have `email_smtp_pass` and
`email_riot_base_url` attributes (and it won't by default, because the default
config impl doesn't set any of the attributes unless email_enable_notifs is
set).

tests/push/test_email.py

@@ -63,8 +63,10 @@ class EmailPusherTests(HomeserverTestCase):
         config.email_smtp_port = 20
         config.require_transport_security = False
         config.email_smtp_user = None
+        config.email_smtp_pass = None
         config.email_app_name = "Matrix"
         config.email_notif_from = "test@example.com"
+        config.email_riot_base_url = None
 
         hs = self.setup_test_homeserver(config=config, sendmail=sendmail)