Use abstract ModelWithCreatedUpdatedFields for Note model

this adds the fields `created_at`, `created_by`, `updated_at` and `updated_by`

program/models.py

@@ -1158,7 +1158,7 @@ class TimeSlot(models.Model):
         return str("".join(s for s in string if s.isdigit()))
 
 
-class Note(ModelWithImageFields):
+class Note(ModelWithImageFields, ModelWithCreatedUpdatedFields):
     timeslot = models.OneToOneField(TimeSlot, on_delete=models.CASCADE, unique=True)
     contributors = models.ManyToManyField(Host, related_name="contributions")
     owner = models.ForeignKey(