Bulk update host field to null for JobEvents

awx/main/tasks.py

@@ -561,6 +561,8 @@ def delete_inventory(self, inventory_id, user_id):
     with ignore_inventory_computed_fields(), ignore_inventory_group_removal(), impersonate(user):
         try:
             i = Inventory.objects.get(id=inventory_id)
+            for host in i.hosts.iterator():
+                host.job_events_as_primary_host.update(host=None)
             i.delete()
             emit_channel_notification(
                 'inventories-status_changed',