Invalid Credentials in K8 cluster

[Moises Emilio Benzan Mora]

Kubernetes master fails to initialize due to not receiving valid credentials for the cluster in order to run kubectl commands.

```
2022-03-16 19:21:25 INFO unit.kubernetes-master/0.juju-log server.go:327 Invoking reactive handler: reactive/kubernetes_master.py:2240:configure_apiserver
2022-03-16 19:21:25 INFO unit.kubernetes-master/0.juju-log server.go:327 Executing ['kubectl', '--kubeconfig=/root/.kube/config', 'get', 'service', '--namespace', 'kube-system', 'k8s-keystone-auth-service', '--output', 'json']
2022-03-16 19:21:26 WARNING unit.kubernetes-master/0.update-status logger.go:60 error: You must be logged in to the server (Unauthorized)
2022-03-16 19:21:26 INFO unit.kubernetes-master/0.juju-log server.go:327 Unable to find k8s-keystone-auth-service service. Will retry
2022-03-16 19:21:27 INFO unit.kubernetes-master/0.juju-log server.go:327 status-set: maintenance: Restarting snap.kube-apiserver.daemon service
```

Artifacts for affected run: https://oil-jenkins.canonical.com/artifacts/3a747bf2-aab3-4b3e-9ed5-0a02701e9ad8/index.html

Affected run: https://solutions.qa.canonical.com/testruns/testRun/3a747bf2-aab3-4b3e-9ed5-0a02701e9ad8

Future affected runs can be tracked here: https://solutions.qa.canonical.com/bugs/bugs/bug/1965330