Automatic merge from submit-queue

Moved kubemark master from Debian to GCI

This PR fixes issue #37484
Kubemark master now runs on GCI instead of Debian, taking it one step closer to a real cluster master.
Primary changes:
1. changing master VM image/OS in kubemark's config-default.sh to debian
2. moving kubelet to systemd from supervisord
3. changing directory for cert/key/csv files from /srv/kubernetes to /etc/srv/kubernetes

cc @kubernetes/sig-scalability-misc  @wojtek-t @gmarek