website: update footer template.

Author: jaywcjlove

template/widget/footer.ejs

@@ -8,6 +8,7 @@
   <a href="https://github.com/roachsinai/krunner-linuxcommands" target="_blank">Krunner</a> |
   <a href="http://jaywcjlove.gitee.io/linux-command/" target="_blank">开源中国Web版</a>
   <br />
+  <a href="https://jaywcjlove.github.io/#/sponsor" target="_blank">打赏捐赠</a> |
   <a href="https://github.com/jaywcjlove/linux-command" target="_blank">Github</a> |
   <a href="https://jaywcjlove.github.io/linux-command/" target="_blank">短地址：https://git.io/linux</a>
   <br />