perf: replace offline mode images

Co-authored-by: Isaac Saunders <contact@eartharoid.me>

public/index.html

@@ -31,7 +31,7 @@
       </style>
       <h1>Error</h1>
       <h2>You need to enable JavaScript to use Mue</h2>
-      <p>Having trouble? Contact us: <a href='https://muetab.com/contact.html'>https://muetab.com/contact</a></p>
+      <p>Having trouble? Contact us: <a href='https://muetab.com/contact'>https://muetab.com/contact</a></p>
     </noscript>
     <div id='root'></div>
   </body>