Fix the link to documentation instructions in the footer

Author: vkucera

_includes/templates/breadcrumbs.liquid

@@ -38,5 +38,5 @@
 Feel like information is missing? Please send your suggestions for updates and improvements to <a href = "mailto:
 [email protected]">docadmin</a>. If you wish to contribute, you're very welcome! Please follow
 the instructions <a
-href="https://aliceo2group.github.io/analysis-framework/docs/gettingstarted/contributingtocode.html">here</a>.
+href="https://aliceo2group.github.io/analysis-framework/docs/gettingstarted/contributingtodocs.html">here</a>.
 </div>