Disable allow_failure for release-environment pipeline

What

Currently, release-environment pipeline has allow_failure set to true, meaning, if QA fails in the downstream pipeline, this won't affect the environment pipeline. We want to disable this so the pipeline fails if QA fails.

With this change, the status and the progress of the stable branches and backport requests depend on the status of the release environment's deployment and QA.

Exit Criteria

• The stable branch's pipeline fails when any job in the start-release-environments-pipeline job fails.
  • Deployment jobs
  • QA job