remove trailing space

the trailing space break the command in zsh at least

docs/getting-started-guides/docker-multinode/master.md

@@ -177,7 +177,7 @@ sudo docker run \
     --volume=/var/run:/var/run:rw \
     --net=host \
     --privileged=true \
-    --pid=host \ 
+    --pid=host \
     -d \
     gcr.io/google_containers/hyperkube:v${K8S_VERSION} /hyperkube kubelet --api-servers=http://localhost:8080 --v=2 --address=0.0.0.0 --enable-server --hostname-override=127.0.0.1 --config=/etc/kubernetes/manifests-multi --cluster-dns=10.0.0.10 --cluster-domain=cluster.local
 ```