Fix link to change logs on landing page

docs/codeql/index.html

@@ -88,7 +88,7 @@
                             latest release of CodeQL...</div>
                     </div>
                     <div class="Subhead border-0">
-                        <a href="codeql-overview/about-codeql">
+                        <a href="codeql-overview/codeql-changelog/">
                             <div class="Subhead-heading f4 text-center">Change logs</div>
                         </a>
                         <div class="Subhead-description">Read about the improvements to the queries, libraries, and tooling in each release...</div>