统一用户头像获取聚合API

<img src="https://avatar.vvhan.com/facebook/:username" />

https://avatar.vvhan.com/facebook/uxiaohan

<img src="https://avatar.vvhan.com/github/:username" />

https://avatar.vvhan.com/github/uxiaohan

<img src="https://avatar.vvhan.com/gravatar/:email" />

https://avatar.vvhan.com/gravatar/1655466387@qq.com

<img src="https://avatar.vvhan.com/instagram/:username" />

https://avatar.vvhan.com/instagram/uxiaohan

<img src="https://avatar.vvhan.com/telegram/:username" />

https://avatar.vvhan.com/telegram/uxiaohan

<img src="https://avatar.vvhan.com/twitter/:username" />

https://avatar.vvhan.com/twitter/uxiaohan

<img src="https://avatar.vvhan.com/youtube/:username" />

https://avatar.vvhan.com/youtube/uxiaohan

<img src="https://avatar.vvhan.com/clearbit/:email" />

https://avatar.vvhan.com/clearbit/uxiaohan

<img src="https://avatar.vvhan.com/deviantart/:username" />

https://avatar.vvhan.com/deviantart/uxiaohan

<img src="https://avatar.vvhan.com/dribbble/:username" />

https://avatar.vvhan.com/dribbble/uxiaohan

<img src="https://avatar.vvhan.com/reddit/:username" />

https://avatar.vvhan.com/reddit/uxiaohan

<img src="https://avatar.vvhan.com/soundcloud/:username" />

https://avatar.vvhan.com/soundcloud/uxiaohan