顶部菜单混合模式+分割菜单，没有子路由，小屏下使用Drawer菜单时，菜单列表消失

[ZhongMingKun]

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Describe the bug

顶部菜单混合模式+分割菜单，没有子路由，小屏下使用Drawer菜单时，菜单列表消失

Reproduction

https://vvbin.cn/thin/next/#/home/welcome 或 https://vvbin.cn/next/#/home/welcome
配置“顶部菜单混合模式+分割菜单”。将浏览器宽度调至1000px以下时，自动启用了Drawer组件渲染菜单。
若该路由下无子路由，Drawer渲染错误

首页下无子菜单（子路由）

菜单渲染失败

System Info

• Operating System: Win10
• Node version: 14.5.0
• Package manager (npm/yarn/pnpm) and version: yarn 1.22.5

[ZhongMingKun]

开启“折叠菜单”后，宽度大于1000px时，省略的菜单无法打开