Invalid Rollout manifest does not fail release task

[donovanmuller]

If a Rollout manifest is invalid and cannot be applied, the task should be marked as failed. Currently it is considered successful. See the two screenshots below, the first for an invalid Rollout and the second for a valid Rollout. Both are successful but the first should be marked as failed.

{
  "data": {
    "message": "Successfully sent promotion event for service rollouts-demo of project argo-rollouts and stage staging: rollout 'rollouts-demo-staging' promoted\n\nName:            rollouts-demo-staging\nNamespace:       argo-rollouts-staging\nStatus:          \u001b[31m✖\u001b[0m Degraded\nMessage:         InvalidSpec: The Rollout \"rollouts-demo-staging\" is invalid: spec.strategy.blueGreen.activeService: Invalid value: \"argo-rollouts-staging-rollouts-demo\": service \"argo-rollouts-staging-rollouts-demo\" not found\nStrategy:        BlueGreen\nReplicas:\n  Desired:       1\n  Current:       0\n  Updated:       0\n  Ready:         0\n  Available:     0\n\nNAME                     KIND     STATUS      AGE  INFO\n⟳ rollouts-demo-staging  Rollout  \u001b[31m✖\u001b[0m Degraded  2s   \n",
    "project": "argo-rollouts",
    "result": "pass",
    "service": "rollouts-demo",
    "stage": "staging",
    "status": "succeeded"
  },
  "id": "3ac68c36-fbca-47f9-be81-627800b95f21",
  "source": "argo-service",
  "specversion": "1.0",
  "time": "2021-04-18T12:47:29.732Z",
  "type": "sh.keptn.event.release.finished",
  "shkeptncontext": "415c120c-c1cd-4ce3-8866-8285ed286e0b",
  "shkeptnspecversion": "0.2.1",
  "triggeredid": "8385db0e-4dd6-42de-9a81-e0668131f399"
}