Add missing report_used_legacy_models() call in combined rules legacy path

Author: cursoragent

src/sentry/incidents/endpoints/organization_alert_rule_index.py

@@ -625,6 +625,7 @@ def get(self, request: Request, organization: Organization) -> Response:
 
         # Legacy path below
         alert_rules = AlertRule.objects.fetch_for_organization(organization, projects)
+        report_used_legacy_models()
 
         issue_rules = Rule.objects.filter(
             status__in=[ObjectStatus.ACTIVE, ObjectStatus.DISABLED],