Wiki: Mark JavaScript modules as deferrable.

Change-Id: Ie5943a1d409e838e5c24c14d61a29378fcb0b6cc
diff --git a/src/main/resources/templates/benki/wiki/wikiPage.html b/src/main/resources/templates/benki/wiki/wikiPage.html
index 3cd522c..e4a7d58 100644
--- a/src/main/resources/templates/benki/wiki/wikiPage.html
+++ b/src/main/resources/templates/benki/wiki/wikiPage.html
@@ -6,7 +6,7 @@
 
 {#head}
 <link rel="stylesheet" type="text/css" href="/web_modules/ContentTools/build/content-tools.min.css" />
-<script type="module" src="/web_modules/elix/define/ExpandablePanel.js"></script>
+<script type="module" src="/web_modules/elix/define/ExpandablePanel.js" defer></script>
 
 <style type="text/css">
   #warning-panel {
@@ -15,7 +15,7 @@
   }
 </style>
 
-<script type="module">
+<script type="module" defer>
   import ContentTools from "/web_modules/ContentTools.js";
 
   window.addEventListener('DOMContentLoaded', function() {