fixup! Update RELEASE.md

link to promo job

Author: nojnhuh

RELEASE.md

@@ -40,6 +40,7 @@ The process for both is as follows:
 1. A PR updating the [registry.k8s.io image list][image list] is opened with the
    SHA digests and tags of the new artifacts from the staging repo.
     - Example PR: https://github.com/kubernetes/k8s.io/pull/7871
+    - After the PR merges, a run of the [promotion job] will kick off.
 1. The artifacts are verified to be available from registry.k8s.io:
     - e.g. the v0.2.0 image and 0.2.0 chart can be verified with the following
       commands:
@@ -55,5 +56,6 @@ The process for both is as follows:
 [chart-staging]: https://console.cloud.google.com/artifacts/docker/k8s-staging-images/us-central1/dra-example-driver/charts%2Fdra-example-driver?inv=1&invt=Abs5-A&project=k8s-staging-images
 [container-staging]: https://console.cloud.google.com/artifacts/docker/k8s-staging-images/us-central1/dra-example-driver/dra-example-driver?inv=1&invt=Abs5-A&project=k8s-staging-images
 [image list]: https://github.com/kubernetes/k8s.io/blob/main/registry.k8s.io/images/k8s-staging-dra-example-driver/images.yaml
+[promotion job]: https://testgrid.k8s.io/sig-k8s-infra-k8sio#post-k8sio-image-promo
 [releases]: https://github.com/kubernetes-sigs/dra-example-driver/releases
 [#wg-device-management]: https://kubernetes.slack.com/archives/C0409NGC1TK