cos-customizer release

for version https://cos-review.git.corp.google.com/c/cos/tools/+/180326
-> https://pantheon.corp.google.com/cloud-build/builds/4e032367-abbd-4c55-a39e-eaf380816cf7?project=google.com:cloud-image-docker-builder&e=13803378

Change-Id: Ie09a3e86e27152187ce03a9b50a87398007598a5
Reviewed-on: https://cos-review.googlesource.com/c/cos/tools/+/182506
Tested-by: Dom Huh <domhuh@google.com>
Reviewed-by: Robert Kolchmeyer <rkolchmeyer@google.com>
Cloud-Build: 228075978874@cloudbuild.gserviceaccount.com <228075978874@cloudbuild.gserviceaccount.com>