Merge branch 'remove-whenever-schedule' into 'master'

Remove unused config/schedule.rb file

[ci skip]

See merge request !2249

config/schedule.rb

-# Use this file to easily define all of your cron jobs.
-#
-# If you make changes to this file, please create also an issue on
-# https://gitlab.com/gitlab-org/omnibus-gitlab/issues . This is necessary
-# because the omnibus packages manage cron jobs using Chef instead of Whenever.
-every 1.hour do
-  rake "ci:schedule_builds"
-end