Doc suggestion: Mutating Webhooks can't set status

[erictune]

@akashrv @droot

Suggested additions to docs about admission webhooks:

"""Validating webhooks run after all mutating webhooks, so you don't need to worry about another webhook changing an object after your validation has accepted it."""

"""You cannot modify or default the status of a resource using a mutating admission webhook. Set initial status in your controller when you first see a new object."""

[fejta-bot]

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[DirectXMan12]

/remove-lifecycle stale

[fejta-bot]

Issues go stale after 90d of inactivity.
Mark the issue as fresh with /remove-lifecycle stale.
Stale issues rot after an additional 30d of inactivity and eventually close.

If this issue is safe to close now please do so with /close.

Send feedback to sig-testing, kubernetes/test-infra and/or fejta.
/lifecycle stale

[DirectXMan12]

/lifecycle frozen

[ptnapoleon]

"""You cannot modify or default the status of a resource using a mutating admission webhook. Set initial status in your controller when you first see a new object."""

Is this true? Where does this limitation come from? This has worked in kubebuilder v2 for us