fix typo

Author: scottaohara

index.html

@@ -6306,7 +6306,7 @@ Change Log
         <section>
           <h4>Substantive changes since moving entirely to the Web Application Working Group (formerly Web Platform WG) (01-Oct-2016)h4>
           <ul>
-            <li>18-Sept-2019: Update `<mark>` element's UIA `LocalizedControlType` and AX `AXRoleDescription`.  See <a href="https://github.com/w3c/html-aam/issues/236">Githug issue 236a>.li>
+            <li>18-Sept-2019: Update `mark` element's UIA `LocalizedControlType` and AX `AXRoleDescription`.  See <a href="https://github.com/w3c/html-aam/issues/236">GitHub issue 236a>.li>
             <li>18-Sept-2019: Update ATK mappings for `summary` and `details` elements. See <a href="https://github.com/w3c/html-aam/issues/142">GitHub issue #142a> and <a href="https://github.com/w3c/html-aam/issues/147">GitHub issue #147a>.li>
             <li>18-Sept-2019: Update MSAA mappings for `sub` and `sup`. See <a href="https://github.com/w3c/html-aam/pull/252">GitHub pull request #252a>.li>
             <li>11-Sept-2019: Update mapping for `menu` to match <a data-cite="html/#the-menu-element">HTML Living Standarda>. Remove element and attribute mappings that are not applicable to `menu` and `menuitem`.  Update mapping of `menu` to `role="list"`. See <a href="https://github.com/w3c/html-aam/issues/188">GitHub issue #188a>.li>