fix(#I12E3S): 更新父级菜单失效

#Comment
comment #I12E3S

#Issue
close https://gitee.com/LongbowEnterprise/dashboard/issues?id=I12E3S

src/admin/Bootstrap.Admin/Views/Admin/Menus.cshtml

@@ -112,7 +112,7 @@
                     </div>
                 </div>
                 <div class="form-group col-sm-6">
-                    <input type="text" class="form-control d-none" id="parentId" data-default-val="0" />
+                    <input type="hidden" class="form-control" id="parentId" data-default-val="0" />
                     <label class="control-label" for="parentName">父级菜单</label>
                     <div class="input-group flex-sm-fill">
                         <input type="text" class="form-control" readonly id="parentName" name="parentName" placeholder="请选择...(可为空)，50字以内" maxlength="50" />

src/admin/Bootstrap.Admin/wwwroot/js/menus.js

@@ -163,6 +163,12 @@ $(function () {
         }
     });
 
+    // clear parentID value
+    // bug https://gitee.com/LongbowEnterprise/dashboard/issues?id=I12E3S
+    $parentMenuName.next().find('button[data-method="clear"]').on('click', function () {
+        $parentMenuID.val('');
+    });
+
     $btnPickIcon.on('click', function () {
         $dialogNew.find('[data-toggle="LgbValidate"] [aria-describedby]').tooltip('hide');
         $dialogNew.hide();