Elimina el plugin Redmine Git Hosting

Finalmente se descarta por los problemas de configuración y potencial
brecha de seguridad al requerir acceso global al puerto ssh.

plugins/redmine_git_hosting/app/workers/githosting_shell_worker.rb

@@ -1,19 +0,0 @@
-class GithostingShellWorker
-  include Sidekiq::Worker
-
-  sidekiq_options queue: :redmine_git_hosting, retry: false
-
-  def self.maybe_do(command, object, options = {})
-    args = [command.to_s, object, options]
-    Sidekiq::Queue.new(:redmine_git_hosting).each do |job|
-      return if job.args == args
-    end
-
-    perform_async(command, object, options)
-  end
-
-  def perform(command, object, options = {})
-    logger.info("#{command} | #{object} | #{options}")
-    RedmineGitHosting::GitoliteWrapper.resync_gitolite(command, object, options)
-  end
-end