This update removes leftover references to an old product type that is no longer used. It helps keep delivery and online sales logic aligned with the current product model, reducing confusion and future maintenance risk.

The product type value `digital` is gone since long time, see 1a1efe3fce12.
This commit removes the leftover occurences of it.

Relatedt to https://github.com/odoo/odoo/issues/25651