Mention system:masters in authz page

[sftim]

This is a Feature Request

What would you like to be added
Update https://kubernetes.io/docs/reference/access-authn-authz/authorization/ to mention the special group system:masters

Why is this needed
Kubernetes has special hard coded treatment for system:masters, but this detail is poorly documented.

Comments
/sig auth security docs

[sftim]

/triage accepted
/priority important-longterm
/help
/language en

[k8s-ci-robot]

@sftim:
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In response to this:

/triage accepted
/priority important-longterm
/help
/language en

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[mrgiles]

@sftim, I've just found only brief mentions of the system:masters group in the RBAC Good Practices and in the Using RBAC pages. Would you like to expand further on the topic or just link to those entries from the Authorization page?

[sftim]

The page to update is https://kubernetes.io/docs/reference/access-authn-authz/authorization/

You can pick the best way to achieve this.

[mrgiles]

/assign

[sftim]

Thanks @mrgiles