[5.4] Show “[ None ]” when Field Group is unassigned in Fields list (joomla#45201)

Author: AdarshSantoria

administrator/components/com_fields/tmpl/fields/default.php

@@ -179,7 +179,7 @@
                                         <?php echo $this->escape($item->type); ?>
                                     </td>
                                     <td>
-                                        <?php echo $this->escape($item->group_title); ?>
+                                        <?php echo !empty($item->group_title) ? $this->escape($item->group_title) : '[ ' . Text::_('JNONE') . ' ]'; ?>
                                     </td>
                                     <td class="small d-none d-md-table-cell">
                                         <?php echo $this->escape($item->access_level); ?>