Refresh project to work on more recent OS/G5K

Several maintenance commits to make deployment work on G5K and Vagrant, including moving to a newer release of Kubespray / Kubernetes.

It mostly works, but some things still don't work well:

• 2 out of 3 links displayed at the end are broken:
  • http://paravance-58.rennes.grid5000.fr:8001/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/#!/login fails with services "kubernetes-dashboard" not found
  • https://paravance-58.rennes.grid5000.fr:6443/api/v1/namespaces/kube-system/services/https:kubernetes-dashboard:/proxy/#!/login fails with services "https:kubernetes-dashboard:" is forbidden: User "system:anonymous" cannot get resource "services/proxy" in API group "" in the namespace "kube-system"
• deploying on vmong5k fails with error: Failed to create domain from /var/lib/libvirt/images/enos_vmong5k/virtual-132-0-2.xml\nerror: unsupported configuration: disk type of 'vdb' does not support ejectable media. This is already fixed in a newer release of Enoslib, but we are still using Enoslib 5.X
• it's not very reliable, sometimes deployment fails between two major steps, apparently because of an empty inventory. The error looks like this:

  File "/home/bjonglez/enos-kubernetes/enos-kubernetes/enos_kubernetes/cli.py", line 123, in deploy
    t.inventory(env=env)
  File "/home/bjonglez/enos-kubernetes/venv/lib/python3.9/site-packages/enoslib/task.py", line 213, in decorated
    r = fn(*args, **kwargs)
  File "/home/bjonglez/enos-kubernetes/enos-kubernetes/enos_kubernetes/tasks.py", line 109, in inventory
    roles = env["roles"]
  File "/usr/lib/python3.9/collections/__init__.py", line 1058, in __getitem__
    raise KeyError(key)
KeyError: 'roles'