[api] Remove all require event

As Event module is now structure in a Rails way the requires are not
longer needed.

src/api/app/controllers/source_controller.rb

@@ -2,7 +2,6 @@
 include ValidationHelper
 
 require 'builder/xchar'
-require 'event'
 
 class SourceController < ApplicationController
   class IllegalRequest < APIException

src/api/app/controllers/webui/user_controller.rb

@@ -1,5 +1,3 @@
-require 'event'
-
 class Webui::UserController < Webui::WebuiController
   before_action :check_display_user, only: [:show, :edit, :list_my, :delete, :confirm, :admin, :lock]
   before_action :require_login, only: [:edit, :save, :index]

src/api/app/models/bs_request.rb

@@ -1,5 +1,4 @@
 require 'xmlhash'
-require 'event'
 
 include MaintenanceHelper
 

src/api/app/models/comment.rb

@@ -1,4 +1,3 @@
-require 'event'
 require 'set'
 
 class Comment < ApplicationRecord

src/api/app/models/update_notification_events.rb

@@ -1,5 +1,3 @@
-require 'event'
-
 class UpdateNotificationEvents
   cattr_accessor :semaphore
 

src/api/config/clock.rb

@@ -1,9 +1,6 @@
 require File.dirname(__FILE__) + '/boot'
 require File.dirname(__FILE__) + '/environment'
 
-# make sure our event is loaded first - the clockwork::event is *not* ours
-require 'event'
-
 require 'clockwork'
 
 module Clockwork

src/api/test/models/event_test.rb

@@ -1,5 +1,4 @@
 require_relative '../test_helper'
-require 'event'
 require 'event_subscription'
 
 class EventTest < ActionDispatch::IntegrationTest