container_prep: use CIPD packages for cros-test

BUG=b:393597613
TEST=build_containers

Change-Id: Iead332199b9f77f0e32a9ec9c53af974c3930bdd
Reviewed-on: https://chromium-review.googlesource.com/c/chromiumos/platform/dev-util/+/6216714
Reviewed-by: Azizur Rahman <azrahman@google.com>
Commit-Queue: Chris DeLaGarza <cdelagarza@google.com>
Tested-by: Chris DeLaGarza <cdelagarza@google.com>
3 files changed