Fix cluster-autoscaler release

• ServiceMonitor cannot install on unexistent namespace
  • Upstream chart installs the serviceMonitor manifest into the monitoring namespace, which does not exist and thus breaks our deployment.
• Update chart due to 1.25 clusters use Policy API deprecation of policy/v1beta1
  • https://kubernetes.io/docs/reference/using-api/deprecation-guide/#poddisruptionbudget-v125

Closes: #25 (closed)