Purpose
=======
Hide non-relevant fields for a portal user. E.G. we want to hide the
notification type, the menu customization... Because those fields
make no sense for a portal user.
Force the non-internal user to receive notifications by emails since
they can not open Discuss.
Task-2508521
Part-of: odoo/odoo#77766
Co-authored-by: nounoubensebia <neb@odoo.com>