Is it possible to disable all scheduled jobs while testing a new release of gitlab

Before upgrading the production gitlab instance, we always test it on a separate machine. I would like to disable all ‘scheduled’ jobs, as I do not want anything to run or deploy something from this test instance. I know how to disable email notifications in the gitlab.rb, but I’m wondering if there is also a possibility to disable all scheduled jobs. Or is the best way to not launch any shared/global gitlab-runners, so scheduled jobs won’t be able to start?

Thanks,
Mariska