fix: the contenttype of the rootobject should not be user editable

apis_core/apis_metainfo/migrations/0008_alter_rootobject_self_contenttype.py

@@ -0,0 +1,26 @@
+# Generated by Django 4.1.11 on 2023-10-11 10:14
+
+from django.db import migrations, models
+import django.db.models.deletion
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("contenttypes", "0002_remove_content_type_name"),
+        ("apis_metainfo", "0007_delete_source"),
+    ]
+
+    operations = [
+        migrations.AlterField(
+            model_name="rootobject",
+            name="self_contenttype",
+            field=models.ForeignKey(
+                blank=True,
+                editable=False,
+                null=True,
+                on_delete=django.db.models.deletion.CASCADE,
+                to="contenttypes.contenttype",
+            ),
+        ),
+    ]

apis_core/apis_metainfo/models.py

@@ -54,7 +54,11 @@ class RootObject(models.Model):
     # triples where the subject's or object's contenttype must be respected (e.g. get all triples
     # where the subject is a Person)
     self_contenttype = models.ForeignKey(
-        ContentType, on_delete=models.deletion.CASCADE, null=True, blank=True
+        ContentType,
+        on_delete=models.deletion.CASCADE,
+        null=True,
+        blank=True,
+        editable=False,
     )
     objects = models.Manager()
     objects_inheritance = InheritanceManager()