about widget: Change class name to work around uBlock bug (Close #276)

layouts/partials/widgets/about.html

@@ -28,7 +28,7 @@
 
       <link itemprop="url" href="{{ $.Site.BaseURL }}">
 
-      <ul class="social-icon" aria-hidden="true">
+      <ul class="network-icon" aria-hidden="true">
         {{ range $.Site.Params.social }}
         {{ $pack := or .icon_pack "fa" }}
         <li>