Use a separate app for registration

apps/registration/apps.py

@@ -0,0 +1,10 @@
+# Copyright (C) 2018-2020 by BDE ENS Paris-Saclay
+# SPDX-License-Identifier: GPL-3.0-or-later
+
+from django.apps import AppConfig
+from django.utils.translation import gettext_lazy as _
+
+
+class RegistrationConfig(AppConfig):
+    name = 'registration'
+    verbose_name = _('registration')