Broken link at docs/eventing/broker-trigger.md

[daisy-ycguo]

Expected Behavior

Broker->Manual Setup
"The ClusterRole is installed with Knative Eventing here."

Here should link to knative/eventing/blob/master/config/200-broker-clusterrole.yaml.

Actual Behavior

Now it links to knative/docs/blob/master/config/200-broker-clusterrole.yaml, which will cause a "page not found" error.

Steps to Reproduce the Problem

Click the link.