dev/ci: remove updater that is causing lockups

Created by: bobheadxi

I have no idea what this is doing - the repos this thing targets don't seem used, and we use Renovate for deploy-sourcegraph-cloud right? This is causing 30+ min lockups in main that are triggering branch locks due to builds stalling for 45+ mins (which is the current threshold).

Closes https://github.com/sourcegraph/sourcegraph/issues/30150