Fix issue comment form and quick-submit (#30623)

1. Rewrite initGlobalEnterQuickSubmit (by the way, remove jQuery)
2. Fix issue comment form layout

web_src/js/features/comp/QuickSubmit.js

@@ -9,9 +9,5 @@ export function handleGlobalEnterQuickSubmit(target) {
     // here use the event to trigger the submit event (instead of calling `submit()` method directly)
     // otherwise the `areYouSure` handler won't be executed, then there will be an annoying "confirm to leave" dialog
     form.dispatchEvent(new SubmitEvent('submit', {bubbles: true, cancelable: true}));
-  } else {
-    // if no form, then the editor is for an AJAX request, dispatch an event to the target, let the target's event handler to do the AJAX request.
-    // the 'ce-' prefix means this is a CustomEvent
-    target.dispatchEvent(new CustomEvent('ce-quick-submit', {bubbles: true}));
   }
 }