Refactor handleCloudInitNotStarted()

/kind feature

The current implementation of handleCloudInitNotStarted() does some checks to guess if cloud-init was successfully or not.

We could improve that by added a `touch /root/preKubeadmCommand-success-HBMM_MACHINEUUID`
and `touch /root/postKubeadmCommand-success-HBMM_MACHINEUUID` at the end of the pre/post Kubeadm commands.

If these files do not exist, then something went wrong.