add base factory into textbooks factory

cms/static/js/pages/textbooks.js

 define(
-    ['js/factories/textbooks', 'common/js/utils/page_factory', 'js/pages/course'],
+    ['js/factories/textbooks', 'common/js/utils/page_factory', 'js/factories/base', 'js/pages/course'],
     function(TextbooksFactory, invokePageFactory) {
         'use strict';
         invokePageFactory('TextbooksFactory', TextbooksFactory);