/kind feature

The web app currently seems to assume that grafana will be accessible via the same ingress as kubeflow under the path /grafana. We have a separated prometheus+grafana that we would like to use instead.

In the web app, I can see that grafanaPrefix is pulled out into the environment.ts file, but I think these vars are only read/replaced at build time and can't be overwritten at run time - I don't know Angular

I think the var needs to be read from the kfserving-models-web-app-config configMap instead? Like APP_PREFIX etc.

@kimwnasptd could you take a look please?