Description of problem:
An example "add-webhooks-unauth.yaml" does not work for me. The example creates a role binding to Role "system:webhook". When I updated the "Role" to "ClusterRole" the example start working in my case.

How reproducible:
Create a buildConfig with webHook and try to manually trigger the webhook with curl. Since 4.16 version it returns "forbidden" error then I applied the "add-webhooks-unauth.yaml" configuration (from the documentation) and it still didn't work. When I updated the "Role" to "ClusterRole" it srtat working.