lib/release: Set GCRIO_PATH_TEST to 'gcr.io/k8s-staging-kubernetes'
lib/release: Set GCRIO_PATH_TEST to 'gcr.io/k8s-staging-kubernetes'

Signed-off-by: Stephen Augustus <f96984fef9637085f0559f1484dfd4e99545cd6e@vmware.com>

kubernetes/release,kubernetes/release