add sidekiq dependancy to GemFile, change deprecated method *_filter by *_action, it is the equivalent since Rails5.2

Author: Guillaume DUPE

Gemfile

@@ -1,3 +1,4 @@
+gem "sidekiq"
 gem 'erubis', '~> 2.7'
 gem "holidays", "~>1.0.3"
 gem "icalendar"

app/controllers/rb_all_projects_controller.rb

@@ -1,7 +1,7 @@
 class RbAllProjectsController < ApplicationController
   unloadable
 
-  before_filter :authorize_global
+  before_action :authorize_global
 
   def statistics
     backlogs_projects = RbCommonHelper.find_backlogs_enabled_active_projects

app/controllers/rb_calendars_controller.rb

@@ -5,7 +5,7 @@ class RbCalendarsController < RbApplicationController
 
   case Backlogs.platform
     when :redmine
-      before_filter :require_admin_or_api_request, :only => :ical
+      before_action :require_admin_or_api_request, :only => :ical
       accept_api_auth :ical
     when :chiliproject
       accept_key_auth :ical