fix broken HTML in header

Author: mojavelinux

src/partials/header-content.hbs

@@ -80,13 +80,13 @@
             <a class="navbar-item" href="#">Asciidoctor Mathematical <small>stem</small></a>
             <a class="navbar-item" href="#">Asciidoctor Prism <small>source highlighter</small></a>
           </div>
-          --}}
-          <a class="navbar-item" href="https://github.com/asciidoctor" target="_blank" rel="noopener">
-            <span class="icon">
-              <svg xmlns="http://www.w3.org/2000/svg"><use href="{{{uiRootPath}}}/img/octicons.svg#symbol-mark-github"></use></svg>
-            </span>
-          </a>
         </div>
+        --}}
+        <a class="navbar-item" href="https://github.com/asciidoctor" target="_blank" rel="noopener">
+          <span class="icon">
+            <svg xmlns="http://www.w3.org/2000/svg"><use href="{{{uiRootPath}}}/img/octicons.svg#symbol-mark-github"></use></svg>
+          </span>
+        </a>
       </div>
     </div>
   </nav>