CASMMON-407: Update prometheus URL to victoria-metrics

[arka-pramanik-hpe]

Summary and Scope

Update prometheus URL to victoria-metrics url because from CSM 1.6 prometheus will be replaced with victoria-metrics.

The end result is that many of the GUI functions do not work correctly as Kiali cannot connect to Prometheus.
This PR corrects the Prometheus URL used by Kiali.

Issues and Related PRs

List and characterize relationship to Jira/Github issues and other pull requests. Be sure to list dependencies.

• Resolves CASMMON-407

Testing

List the environments in which these changes were tested.

Tested on:

Fanta

Test description:

Prometheus url is replaced with vmselect in victoria-metrics from CSM-1.6
 
ncn-m001:/mnt/developer/shreni # kubectl get pod -n sysmgmt-health | grep select
vmselect-vms-0                                                   1/1     Running            0          8m53s
vmselect-vms-1                                                   1/1     Running            0          8m53s
 
-------------------------------------------------------------------------------------------------------------------
 
ncn-m001:/mnt/developer/shreni # kubectl -n istio-system get kiali -o yaml | yq4 eval '.. | select(has("prometheus"))'
grafana:
  url: https://grafana.cmn.fanta.hpc.amslabs.hpecorp.net/
prometheus:
  url: http://vmselect-vms.sysmgmt-health.svc.cluster.local:8481/select/0/prometheus
tracing:
  enabled: false

---

[spillerc-hpe]

Have other features of Kiali beyond the mesh topology graph been tested? Presumably the Inbound/Outbound traffic metrics still work?

[shreni123]

Have other features of Kiali beyond the mesh topology graph been tested? Presumably the Inbound/Outbound traffic metrics still work?

@spillerc-hpe , I can see Inbound/Outbound traffic metrics, will add screenshots for that as well. Thanks!

[dborman-hpe]

LGTM