tests/k8s/Vagrantfile: reset kubeadm before init
tests/k8s/Vagrantfile: reset kubeadm before init

kubeadm init sometimes fails when starting the K8s Tests Vagrant VM
because files exist in /var/lib/kubelet, so reset kubeadm before
initializing it to clear any state that might have been stored there by
installation of kubelet and other K8s-related processes.

Signed-off by: Ian Vernon <ian@covalent.io>

michi-covalent/cilium,cilium/cilium,mskarbek/cilium,cilium/cilium,scanf/cilium,michi-covalent/cilium,mskarbek/cilium,cilium/cilium,gumpt/cilium,eloycoto/cilium,tgraf/cilium,gumpt/cilium,cilium/cilium,scanf/cilium,mskarbek/cilium,tklauser/cilium,cilium/cilium,mskarbek/cilium,tklauser/cilium,gumpt/cilium,eloycoto/cilium,michi-covalent/cilium,eloycoto/cilium,cilium-team/cilium,gumpt/cilium,scanf/cilium,gumpt/cilium,eloycoto/cilium,scanf/cilium,eloycoto/cilium,tgraf/cilium,michi-covalent/cilium,eloycoto/cilium,tgraf/cilium,tklauser/cilium,michi-covalent/cilium,tgraf/cilium,eloycoto/cilium,tklauser/cilium,scanf/cilium,gumpt/cilium,scanf/cilium,tgraf/cilium,gumpt/cilium,tklauser/cilium,mskarbek/cilium,tgraf/cilium,mskarbek/cilium,cilium-team/cilium,scanf/cilium