fix: note image should allow null values

program/serializers.py

@@ -699,7 +699,9 @@ class NoteLinkSerializer(serializers.ModelSerializer):
 
 class NoteSerializer(serializers.ModelSerializer):
     contributors = serializers.PrimaryKeyRelatedField(queryset=Host.objects.all(), many=True)
-    image = serializers.PrimaryKeyRelatedField(queryset=Image.objects.all(), required=False)
+    image = serializers.PrimaryKeyRelatedField(
+        queryset=Image.objects.all(), required=False, allow_null=True
+    )
     links = NoteLinkSerializer(many=True, required=False)
     timeslot = serializers.PrimaryKeyRelatedField(queryset=TimeSlot.objects.all(), required=False)