use github avatar

Author: Huxpro

_config.yml

@@ -79,7 +79,7 @@ ga_domain: huangxuan.me
 # Sidebar settings
 sidebar: true                           # whether or not using Sidebar.
 sidebar-about-description: "黄玄，前端娱乐圈 NPC，编程语言/编译器初心者 <br> An UI/Frontend dev & designer accidentally growing into a compiler/PL hacker."
-sidebar-avatar: /img/avatar-hux-ny.jpg      # use absolute URL, seeing it's used in both `/` and `/about/`
+sidebar-avatar: https://github.com/Huxpro.png # use absolute URL, seeing it's used in both `/` and `/about/`