Remove debug print in kubectl.sh

Removes a debug print that (it seems to me) was added in erro
as part of PR #3046 / commit c3efef8.

cluster/kubecfg.sh

@@ -106,5 +106,4 @@ if [[ -n "${KUBE_MASTER_IP-}" && -z "${KUBERNETES_MASTER-}" ]]; then
   export KUBERNETES_MASTER=https://${KUBE_MASTER_IP}
 fi
 
-echo "Running: " "${kubecfg}" "${auth_config[@]:+${auth_config[@]}}" "${@}" >&2
 "${kubecfg}" "${auth_config[@]:+${auth_config[@]}}" "${@}"