Revert "Switch to only using duotone FontAwesome"

This reverts commit f4d519bbd1.

layouts/_default/baseof.html

@@ -127,7 +127,7 @@
         </div>
       </div>
     </div>
-    {{ $fajs := resources.Get "scripts/fontawesome/duotone.min.js" }}
+    {{ $fajs := resources.Get "scripts/fontawesome/all.min.js" }}
     {{ $jqueryjs := resources.Get "scripts/jquery/jquery.min.js" }}
     {{ $popperjs := resources.Get "scripts/popper/popper.min.js" }}
     {{ $twbsjs := resources.Get "scripts/bootstrap/bootstrap.min.js" }}