Explore the use of prom metrics to find pvc utilization instead of running df and requiring a pod. The motivation is, for DVM we do not have an explicit requirement on the stage pod, while intelligent PV resize does. To make full use of it, we should provide users with options when running DVM

It's not clear what the right way to accomplish this would be, so we'll need to decide on an approach/design, and also evaluate how important this actually is.