微信菜单接口获取失败

    /**
     * 获取菜单
     *
     * @return array
     */
    public function get($agentId)
    {
        $menus = $this->http->get(self::API_GET.'?agentid='.$agentId);

        return empty($menus['menu']['button']) ? array() : $menus['menu']['button'];
    }


```
{
"errcode": 0,
"errmsg": "ok",
"button": []
}
```

貌似微信返回格式变了，现在`$menus['menu']['button']`都是获取为空