Remove not working constraint

aleksis/apps/alsijil/migrations/0020_documentation_extramark_colour_bg_and_more.py

@@ -89,8 +89,4 @@ class Migration(migrations.Migration):
             model_name='newpersonalnote',
             constraint=models.CheckConstraint(check=models.Q(models.Q(('note', ''), _negated=True), ('extra_mark__isnull', False), _connector='OR'), name='unique_absence_per_documentation'),
         ),
-        migrations.AddConstraint(
-            model_name='documentation',
-            constraint=models.CheckConstraint(check=models.Q(('amends__isnull', True), ('course__isnull', True), _negated=True), name='either_course_or_amends'),
-        ),
     ]

aleksis/apps/alsijil/models.py

@@ -511,12 +511,8 @@ class Documentation(CalendarEvent):
     class Meta:
         verbose_name = _("Documentation")
         verbose_name_plural = _("Documentations")
-        constraints = [
-            models.CheckConstraint(
-                check=~Q(course__isnull=True, amends__isnull=True),
-                name="either_course_or_amends",
-            ),
-        ]
+        # should check if object has either course or amends,
+        # which is not possible via constraint, because amends is not local to Documentation
 
     @classmethod
     def get_for_coursebook(