Automatic merge from submit-queue (batch tested with PRs 50386, 50374, 50444, 50382)
Add grabbing Cluster Autoscaler metrics in e2e tests
This adds:
- collecting metrics from Cluster Autoscaler before & after e2e test run
- --include-cluster-autoscaler opt-in flag
- passing external cluster client to MetricsGrabber (required for Kubemark setup, as Cluster Autoscaler doesn't run on master in this case)