migrate projects:issues:show to static bundle

app/assets/javascripts/dispatcher.js

@@ -56,12 +56,7 @@ import SearchAutocomplete from './search_autocomplete';
           break;
         case 'projects:merge_requests:index':
         case 'projects:issues:index':
-          shortcut_handler = true;
-          break;
         case 'projects:issues:show':
-          import('./pages/projects/issues/show')
-            .then(callDefault)
-            .catch(fail);
           shortcut_handler = true;
           break;
         case 'dashboard:milestones:index':

app/assets/javascripts/pages/projects/issues/show/index.js

-
 /* eslint-disable no-new */
+
 import initIssuableSidebar from '~/init_issuable_sidebar';
 import Issue from '~/issue';
 import ShortcutsIssuable from '~/shortcuts_issuable';
 import ZenMode from '~/zen_mode';
 
-export default () => {
+document.addEventListener('DOMContentLoaded', () => {
   new Issue();
   new ShortcutsIssuable();
   new ZenMode();
   initIssuableSidebar();
-};
+});