Automatic merge from submit-queue (batch tested with PRs 44687, 44689, 44661)

Retry in get-kube.sh to avoid download flakes.

GCS has up to 2% 5xx rates, so retrying is critical.

This is currently failing about 8 times per day [according to the dashboard](https://storage.googleapis.com/k8s-gubernator/triage/index.html?test=Extract#be2f33fb1e6dd2389d12). It could be backported to reduce the flake rate.

Relase note:
```release-note
NONE
```