Completely remove the `django.contrib.sites` dependency in the next major release

[danielmursa-dev]

Thema / Theme

API

Omschrijving / Description

Continue of the main issue #59
Remove django.contrib.sites dependency in:

• Open Zaak
• Open Notificaties
• Objects API

before the next major release

Toegevoegde waarde / Added value

No response

Aanvullende opmerkingen / Additional context

No response