add broken link

Author: doomy

templates/index.html

@@ -39,7 +39,7 @@ <h4 style="margin: 0;">Discord</h4>
     </div>
     <hr>
     <h4 style="margin: 0;">Forums</h4>
-    <p>Visit <a href="rust-audio.discourse.group">the RustAudio forums</a> on Discourse</p>
+    <p>Visit <a href="//rust-audio.discourse.group">the RustAudio forums</a> on Discourse</p>
 </section>
 
 <hr>