优化一下博客的性能

themes/Ying/layouts/partials/header.html

@@ -5,7 +5,7 @@
         <div class="header">
             <div class="header-top">
                 <div class="header-avatar load-memos-editor" id="theme-toggle-avatar">
-                    <img src="{{ .Site.Params.author.avatar }}" class="blog-img" width="80" height="80" alt="{{ .Site.Title }}" />
+                    <img src="{{ .Site.Params.author.avatar }}" class="blog-img" width="80" height="80" alt="{{ .Site.Title }}" decoding="async" fetchpriority="high" />
                     <div class="avatar-theme-tip">
                         点击头像切换昼夜
                     </div>