Update quick_start.md (#2072)

master link not work, i change it to stable
Signed-off-by: Derek Wang <whynowy@gmail.com>

docs/quick_start.md

@@ -7,7 +7,7 @@ The Argo Workflow controller will need to be configured to listen for Workflow o
   (See [this](https://github.com/argoproj/argo-workflows/blob/master/docs/managed-namespace.md) link.) 
   The Workflow Controller will need to be installed either in a cluster-scope configuration (i.e. no "--namespaced" argument) so that it has visiblity to all namespaces, or with "--managed-namespace" set to define "argo-events" as a namespace it has visibility to. To deploy Argo Workflows with a cluster-scope configuration you can use this installation yaml file:
 
-        kubectl apply -n argo -f https://raw.githubusercontent.com/argoproj/argo-workflows/master/manifests/install.yaml
+        kubectl apply -n argo -f https://raw.githubusercontent.com/argoproj/argo-workflows/stable/manifests/install.yaml
 
 1. Make sure to have the eventbus pods running in the namespace. Run following command to create the eventbus.