Automatic merge from submit-queue
Kubelet: add kubeGenericRuntimeManager for new runtime API
Part of #28789. Add `kubeGenericRuntimeManager` for kubelet new runtime API #17048.
Note that:
- To facilitate code reviewing, #28396 is splited into a few small PRs. This is the first part.
- This PR also fixes some syntax errors in `api.proto`.
- This PR is depending on #29811 (already merged).
CC @yujuhong @Random-Liu @kubernetes/sig-node