chore: update json example fields

Author: jbarreau

src/_example/django/django_demo/.forestadmin-schema.json

@@ -3525,6 +3525,7 @@
         "stack": {
             "engine": "python",
             "engine_version": "3.11.3"
-        }
+        },
+        "schemaFileHash": "94008f891a07a15668f272455796cec49a8c8526"
     }
 }