Remove usage of deprecated Model and Serializer fields (#1663)

api/funkwhale_api/moderation/models.py

@@ -3,7 +3,7 @@ import uuid
 
 from django.contrib.contenttypes.fields import GenericForeignKey, GenericRelation
 from django.contrib.contenttypes.models import ContentType
-from django.contrib.postgres.fields import JSONField
+from django.db.models import JSONField
 from django.db import models
 from django.db.models.signals import pre_save
 from django.dispatch import receiver