Revert "Update include.html (#275)" (#277)

This reverts commit 7eea16c.

assets/include.html

@@ -16,7 +16,7 @@
      var header = $(`<div id="header_wrap" class="outer">
         <header class="inner">
           
-            <a id="forkme_banner" href="javascript:void(0)">Fork on GitHub</a>
+            <a id="forkme_banner" href="https://github.com/Beluga-lang/McTT">Fork on GitHub</a>
           ${h1elem.outerHTML}
         </header>
     </div>`);