[#3362] Add a migration to clean up urls

src/openforms/submissions/migrations/0079_cleanup_urls.py

@@ -0,0 +1,29 @@
+# Generated by Django 3.2.21 on 2023-11-16 14:57
+from django.db import migrations
+from django.db.migrations.state import StateApps
+from django.db.backends.base.schema import BaseDatabaseSchemaEditor
+
+from furl import furl
+
+
+def cleanup_submission_urls(
+    apps: StateApps, schema_editor: BaseDatabaseSchemaEditor
+) -> None:
+
+    Submission = apps.get_model("submissions", "Submission")
+
+    for submission in Submission.objects.all():
+        f = furl(submission.form_url)
+        f.remove(fragment=True)
+        submission.form_url = f.url
+
+        submission.save()
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ("submissions", "0078_submission_finalised_registration_backend_key"),
+    ]
+
+    operations = [migrations.RunPython(cleanup_submission_urls)]