ci: enable debug log for kubelet

Default log level for kubelet is 2, changes it to 4 will get more detail logs.
https://github.com/kubernetes/community/blob/master/contributors/devel/sig-instrumentation/logging.md

Fixes: #3039

Signed-off-by: bin liu <bin@hyper.sh>

integration/kubernetes/init.sh

@@ -113,6 +113,12 @@ sudo cp "/etc/kubernetes/admin.conf" "$HOME/.kube/config"
 sudo chown $(id -u):$(id -g) "$HOME/.kube/config"
 export KUBECONFIG="$HOME/.kube/config"
 
+# enable debug log for kubelet
+sudo sed -i 's/.$/ --v=4"/' /var/lib/kubelet/kubeadm-flags.env
+echo "Kubelet options:"
+sudo cat /var/lib/kubelet/kubeadm-flags.env
+sudo systemctl daemon-reload && sudo systemctl restart kubelet
+
 kubectl get nodes
 kubectl get pods