Fix issue rebalance rescheduler cron job

This is meant to run every 15 minutes and not every minute, every 15
hours

config/initializers/1_settings.rb

@@ -589,7 +589,7 @@ Settings.cron_jobs['batched_background_migrations_worker'] ||= Settingslogic.new
 Settings.cron_jobs['batched_background_migrations_worker']['cron'] ||= '* * * * *'
 Settings.cron_jobs['batched_background_migrations_worker']['job_class'] = 'Database::BatchedBackgroundMigrationWorker'
 Settings.cron_jobs['issues_reschedule_stuck_issue_rebalances'] ||= Settingslogic.new({})
-Settings.cron_jobs['issues_reschedule_stuck_issue_rebalances']['cron'] ||= '* 0/15 * * *'
+Settings.cron_jobs['issues_reschedule_stuck_issue_rebalances']['cron'] ||= '*/15 * * * *'
 Settings.cron_jobs['issues_reschedule_stuck_issue_rebalances']['job_class'] = 'Issues::RescheduleStuckIssueRebalancesWorker'
 Settings.cron_jobs['clusters_integrations_check_prometheus_health_worker'] ||= Settingslogic.new({})
 Settings.cron_jobs['clusters_integrations_check_prometheus_health_worker']['cron'] ||= '0 * * * *'