Automatic merge from submit-queue (batch tested with PRs 50198, 49051, 48432)

move KubeletConfiguration out of componentconfig API group

I'm splitting #44252 into more manageable steps. This step moves the types and updates references.

To reviewers: the most important changes are the removals from pkg/apis/componentconfig and additions to pkg/kubelet/apis/kubeletconfig. Almost everything else is an import or name update.

I have one unanswered question: Should I create a whole new api scheme for Kubelet APIs rather than register e.g. a kubeletconfig group with the default runtime.Scheme instance? This feels like the right thing, as the Kubelet should be exposing its own API, but there's a big fat warning not to do this in `pkg/api/register.go`. Can anyone answer this?