Merge pull request #495 from abays/rm_ds_trigger_wf

Remove reference to deleted downstream workflow

The workflow referenced no longer exists in CIFMW [1] and throws an error whenever someone comments on a PR.
[1] openstack-k8s-operators/ci-framework#2703

Reviewed-by: John Fulton <[email protected]>

Author: softwarefactory-project-zuul[bot]