docs/topindex.html: Fix typo in "Glossary" heading.

docs/templates/topindex.html

@@ -88,7 +88,7 @@
     </td>
     <td width="40%" style="padding-left:2em;">
       <p class="biglink">
-        <a class="biglink" href="{{ pathto("reference/glossary") }}">Glosssary</a><br/>
+        <a class="biglink" href="{{ pathto("reference/glossary") }}">Glossary</a><br/>
         <span class="linkdescr">MicroPython terms explained</span>
       </p>
       <p class="biglink">