📖 Reword and list which deployments have to be edited for exp features.

[johannesfrey]

What this PR does / why we need it:
This paragraph in the section describing describing the experimental features explains how to enable/disable features in a running mgmt cluster. Trying this for the ClusterToplogy feature flag revealed that the flag must also to be enabled for KCP. Otherwise the Webhook for KubeadmControlPlaneTemplate will deny the request. See: https://github.com/kubernetes-sigs/cluster-api/blob/main/controlplane/kubeadm/api/v1beta1/kubeadmcontrolplanetemplate_webhook.go#L59

It might make sense for a user to get a list which deployments have to be edited for which feature. Not sure if this is the best way to communicate this or if this should rather be put into the corresponding sections of the experimental features. Up for suggestions 🙂.

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Fixes #

/area documentation

_{Johannes Frey <johannes.frey@mercedes-benz.com>, Mercedes-Benz Tech Innovation GmbH (Provider Information)}

[killianmuldoon]

Thanks for doing this!

/lgtm

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: 1a052dd1ea941288e9d358b87acd428a0874698f

[sbueringer]

Thx, nice improvement!

Just once suggestion

[killianmuldoon]

Thanks for the update! Could you squash the commits?

[sbueringer]

Thx!

Also good to know this documentation exists. Will point folks there in the future, we're getting this asked often..

/lgtm
/approve

[k8s-ci-robot]

LGTM label has been added.

Git tree hash: d718e613e0b39b029b552fb1313a549b4dac09aa

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: sbueringer

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• docs/OWNERS [sbueringer]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[killianmuldoon]

/cherry-pick release-1.5

[k8s-infra-cherrypick-robot]

@killianmuldoon: new pull request created: #9205

In response to this:

/cherry-pick release-1.5

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.