kubeadm init: wait-control-pane timeout on Ubuntu 20.04

After a fresh install on a new node, I’ve had a timeout error on `[wait-control-pane]`. The exact issue is documented here: https://github.com/kubernetes/kubeadm/issues/2559

Based on this comment: https://github.com/kubernetes/kubeadm/issues/2559#issuecomment-907623405 simply adding --cgroup-driver=cgroupfs to the KUEBELET_KUBECONFIG_ARGSin the /etc/systemd/system/kubelet.service.d/10-kubeadm.conf file fixed my issues because docker is using that control group driver as mentioned in the above comment.

I’m leaving this note here because I’m about to add some slave nodes this year on my cluster and will reference back here