Update kubernetes client to latest version

I missed this in !7 (merged).

The main reason is for the client to be able to create multiple manifests from a single file, which is what I'm doing for storage classes here https://gitlab.cern.ch/ai/it-puppet-hostgroup-cloud_monitoring/-/blob/qa/code/files/rally/scenarios/magnum/manifests/k8s-cvmfs-storage.yaml.

Keeping this WIP because I will try making a change to the cluster timeouts tomorrow that might help with the clusters not being deleted. Then the two changes can be released in a one go rather than doing two releases.