Upgrade kube-prometheus-stack to chart version 52.0.0 and app version 0.68.0

No problems deploying Prometheus Helm chart to Proxmox VE K3s Kubernetes cluster via Helm Chart and Flux V2 reconciliation in a GitOps approach.
Helm Chart 51.10.0
Helm Chart 52.0.0
0.68.0 / 2023-09-08