remove unnecessary task

lib/tasks/gitlab/write_hook.rake

-namespace :gitlab do
-  namespace :gitolite do
-    desc "GITLAB | Write GitLab hook for gitolite"
-    task :write_hooks => :environment  do
-      gitolite_hooks_path = File.join(Gitlab.config.git_hooks_path, "common")
-      gitlab_hooks_path = Rails.root.join("lib", "hooks")
-      gitlab_hook_files = ['post-receive']
-
-      gitlab_hook_files.each do |file_name|
-        source = File.join(gitlab_hooks_path, file_name)
-        dest = File.join(gitolite_hooks_path, file_name)
-
-        puts "sudo -u root cp #{source} #{dest}".yellow
-        `sudo -u root cp #{source} #{dest}`
-
-        puts "sudo -u root chown git:git #{dest}".yellow
-        `sudo -u root chown git:git #{dest}`
-      end
-    end
-  end
-end