Automatic merge from submit-queue Node E2E: Disable kubenet for local node e2e test. After https://github.com/kubernetes/kubernetes/pull/28196, we must manually setup cni and nsenter in local node to run `make test_e2e_node`, which may not be necessary for local development. I've tried to move cni downloading logic into `BeforeSuite`, however it is still hard to figure out who should install nsenter, manually installed by every developer? in the `setup_host.sh` script? in `BeforeSuite`? This PR: * Added a flag to disable kubenet and disabled kubenet in local test. * Cleaned up the CNI installation logic a bit. /cc @yujuhong @freehan []()