[docs] Update docs to match actuall required settings to perform an unsafe u…

[Flowkap]

Update docs to match actuall required settings to perform an unsafe upgrade using cluster.yml playbook.

Relates to:

• During upgrade, Kubespray does not update /etc/kubernetes/manifests #4736
• Cannot upgrade k8s cluster using cluster.yml, unless upgrade_cluster_setup is set to true #4139

What type of PR is this?

/kind documentation

What this PR does / why we need it:

Which issue(s) this PR fixes:
Fixes #4736
Fixes #4139

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[Flowkap]

Ok. It might have been my missing secondary email (added to github mailing list as well) This comment should retrigger the cla check bot right?

---

It did ^^

[jklare]

Thanks a lot for this patch! I walked through the code a while ago but did not find the right argument to trigger this.

[Flowkap]

Thanks a lot for this patch! I walked through the code a while ago but did not find the right argument to trigger this.

I mean if its intentional the doc update should suffice. ALthough to be honest i'm, not sure why cluster.yml would actually do everything else but this. Didn't find an explanation for it. Maybe its generally not suggested to upgrade the cluster internal services non gracefully. Which might be fine. Anyway with the suggested doc change one can at least use the cluster.yml as its described roughly. :)

[Miouge1]

Thank you for your contribution

/lgtm
/approve

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[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Flowkap, Miouge1

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