`update-init-script` was listed two times. removed one without explanation.

doc/update/8.2-to-8.3.md

@@ -99,8 +99,6 @@ sudo -u git -H bundle exec rake db:migrate RAILS_ENV=production
 # Clean up assets and cache
 sudo -u git -H bundle exec rake assets:clean assets:precompile cache:clear RAILS_ENV=production
-# Update init.d script
-sudo cp lib/support/init.d/gitlab /etc/init.d/gitlab
 ```
 ### 7. Update configuration files