erp5_officejs_ui_test: minor check before assert text present

bt5/erp5_officejs_ui_test/PathTemplateItem/portal_tests/officejs_ui_texteditor_zuite/testOfficeJSTextEditorErp5Synchronization.zpt

@@ -344,6 +344,11 @@
   <td>${base_url}/web_page_module/Zuite_waitForActivities</td>
   <td></td>
 </tr>
+<tr>
+  <td>waitForElementPresent</td>
+  <td>//pre</td>
+  <td></td>
+</tr>
 <tr>
   <td>assertTextPresent</td>
   <td>Done.</td>