Default CNI to enabled, even for Docker runtime

[afbjorklund]

With the release of cri-dockerd 0.2.5, it now defaults to CNI... So it should be recommended, for all runtimes and single-node.

Previously it was only enabled for runtimes using CRI, such as containerd and cri-o, or multi-node. But now, also for docker.

---

This also applies to "none" driver, which has some weird special case (breaking containerd!)

From before, the default CNI plugin is "kindnet" for KIC and multi-node and "bridge" otherwise.

To be conservative with ancient versions, it can use the dockershim change point (1.24.0-alpha.2)

It was suggested before: #6094 (to use CNI), but then it was regarded as overkill (similar to CRI)

---

• Docs: Usage of the alternative CRI-O runtime #2207
• containerd and crio should default to --network-plugin-cni --enable-default-cni #3567

Basically, rules and interfaces only applied to "others"...

Now crictl and /opt/cni/bin are needed everywhere.

[afbjorklund]

This also means that installing CNI needs to be added to the documentation, for "none" driver:

https://minikube.sigs.k8s.io/docs/drivers/none/

But it needed that for containerd and cri-o, anyway... Currently they both output an ugly warning:

                // default container runtime varies, starting with Kubernetes 1.24 - assume that only the default container runtime has been tested
                rtime := viper.GetString(containerRuntime)
                if rtime != constants.DefaultContainerRuntime && rtime != defaultRuntime(getKubernetesVersion(nil)) {
                        out.WarningT("Using the '{{.runtime}}' runtime with the 'none' driver is an untested configuration!", out.V{"runtime": rtime})
                }

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/lifecycle rotten

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/close not-planned

[k8s-ci-robot]

@k8s-triage-robot: Closing this issue, marking it as "Not Planned".

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The Kubernetes project currently lacks enough active contributors to adequately respond to all issues and PRs.

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• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
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/close not-planned

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