Geo: create SystemCheck to detect incorrect enable/disable jobs in Sidekiq Cron

While debugging an issue with a customer, we saw that the sidekiq cron jobs, that triggers the backfilling were disabled on the secondary node. For some reason the cronjob that keeps this configuration up-to-date failed as well. The solution was to restart gitlab (which triggers the verification to re-run).

The wrong sidekiq cron jobs can be automatically detected and we can provide suggestion to restart the server.