ECOM-3760 fix editors not showing up on subsection config popup for self-paced course

cms/static/js/spec/views/pages/course_outline_spec.js

@@ -787,6 +787,8 @@ define(["jquery", "common/js/spec_helpers/ajax_helpers", "common/js/components/u
                     outlinePage.$('.outline-subsection .configure-button').click();
                     expect($(".edit-settings-release").length).toBe(0);
                     expect($(".grading-due-date").length).toBe(0);
+                    expect($(".edit-settings-grading").length).toBe(1);
+                    expect($(".edit-staff-lock").length).toBe(1);
                 });
 
                 it('can select valid time', function() {

cms/static/js/views/modals/course_outline_modals.js

@@ -770,7 +770,7 @@ define(['jquery', 'backbone', 'underscore', 'gettext', 'js/views/baseview',
             if (course.get('self_paced')) {
                 editors = _.without(editors, ReleaseDateEditor, DueDateEditor);
                 _.each(tabs, function (tab) {
-                    tab.editors = _.without(editors, ReleaseDateEditor, DueDateEditor);
+                    tab.editors = _.without(tab.editors, ReleaseDateEditor, DueDateEditor);
                 });
             }
             return new SettingsXBlockModal($.extend({