fix(segments): add migration to set version on existing segments (#4315)

api/segments/migrations/0025_set_default_version_on_segment.py

@@ -0,0 +1,23 @@
+# Generated by Django 3.2.25 on 2024-07-09 10:41
+from django.apps.registry import Apps
+from django.db import migrations
+from django.db.backends.base.schema import BaseDatabaseSchemaEditor
+
+
+def set_default_segment_version(
+    apps: Apps,
+    schema_editor: BaseDatabaseSchemaEditor,
+) -> None:
+    segment_model_class = apps.get_model("segments", "Segment")
+    segment_model_class.objects.filter(version__isnull=True).update(version=1)
+
+
+class Migration(migrations.Migration):
+
+    dependencies = [
+        ('segments', '0024_add_timestamps_to_segments'),
+    ]
+
+    operations = [
+        migrations.RunPython(set_default_segment_version, reverse_code=migrations.RunPython.noop),
+    ]