Update Rakefile to use new Rubocop class name
Update Rakefile to use new Rubocop class name

acollarve/sensu-plugins-mesos,andrelaszlo/sensu-plugins-mesos,apognu/sensu-plugins-mesos,lusid/sensu-plugins-mesos,oskar-flores/sensu-plugins-mesos,sensu-plugins/sensu-plugins-mesos