TLS-626 Trigger promote with e2e tests (#165334)

## Summary
This PR calls the pipeline introduced on
https://github.com/elastic/gpctl/pull/167 which calls the e2e tests
before updating serverless gitops.

The previous change which was introduced on the commits below, used
gpctl to update the image tags for kibana on the controller. This change
resulted in skipping the part where the e2e tests were being run 😬


bf148fb35f

3cfbf24190

The present PR fixes this, by using the new pipeline which includes the
e2e tests introduced on https://github.com/elastic/gpctl/pull/167

.buildkite/scripts/steps/artifacts/docker_image.sh

@@ -98,12 +98,14 @@ steps:
   - label: ":argo: Update kibana image tag for kibana-controller using gpctl"
     async: true
     branches: main
-    trigger: gpctl-promote
+    trigger: gpctl-promote-with-e2e-tests
     build:
       env:
         SERVICE_COMMIT_HASH: "$GIT_ABBREV_COMMIT"
+        SERVICE: kibana-controller
+        NAMESPACE: kibana-ci
+        IMAGE_NAME: kibana-serverless
         REMOTE_SERVICE_CONFIG: https://raw.githubusercontent.com/elastic/serverless-gitops/main/gen/gpctl/kibana/dev.yaml
-
 EOF
 
 else