Redirect IO streams to prevent hanging

https://en.wikipedia.org/wiki/Nohup#Overcoming_hanging

https://gitlab.com/gitlab-org/gitlab-runner/issues/2880

lib/gitlab/ci/templates/Auto-DevOps.gitlab-ci.yml

@@ -798,7 +798,7 @@ rollout 100%:
     echo "Checking Tiller..."
 
     export HELM_HOST=":44134"
-    tiller -listen ${HELM_HOST} -alsologtostderr &
+    tiller -listen ${HELM_HOST} -alsologtostderr > /dev/null 2>&1 &
     echo "Tiller is listening on ${HELM_HOST}"
 
     if ! helm version --debug; then