add removeButton element for description

backstage/static/js/blockElements.js

@@ -27,13 +27,16 @@ function getdescElements(blockDiv) {
   const descTextArea = document.createElement("TEXTAREA");
   descTextArea.setAttribute("type", "text");
   const descInputButton = document.createElement('button');
+  const removeButton = document.createElement('button');
   descInputButton.textContent = 'Description新增/修改';
+  removeButton.textContent = 'Description刪除';
   blockDiv.appendChild(descDiv);
-  descDiv.append(p, descTextArea, descInputButton);
+  descDiv.append(p, descTextArea, descInputButton, removeButton);
   return {
     p: p,
     descTextArea: descTextArea,
-    descInputButton: descInputButton
+    descInputButton: descInputButton,
+    descRemoveButton: removeButton,
   };
 }