Vendor in Auto-DevOps.gitlab-ci.yml to resolve review apps not re-deployable

vendored from https://gitlab.com/gitlab-org/gitlab-ci-yml/merge_requests/188

changelogs/unreleased/50853-vendor-auto-devops-gitlab-ci-yml-to-resolve-redeploying-deleted-app-gives-helm-error.yml

+---
+title: 'Auto-DevOps.gitlab-ci.yml: fix redeploying deleted app gives helm error'
+merge_request: 21429
+author:
+type: fixed

vendor/gitlab-ci-yml/Auto-DevOps.gitlab-ci.yml

@@ -825,7 +825,7 @@ rollout 100%:
     fi
 
     if [[ -n "$(helm ls -q "^$name$")" ]]; then
-      helm delete "$name"
+      helm delete --purge "$name"
     fi
   }