chore: replace broken links

content/blog/2014-09-setting-openstreetmap-as-default-in-thunderbird-contacts.md

@@ -34,4 +34,4 @@ Restart Thunderbird and test again with an existing contact. By clicking on the
 [1]: /uploads/tb-map-contact.png
 [2]: http://openstreetmap.org
 [3]: https://support.mozilla.org/en-US/kb/config-editor
-[4]: https://developer.mozilla.org/en-US/docs/Mozilla/Thunderbird/Hidden_prefs
+[4]: http://web.archive.org/web/20140904073922/https://developer.mozilla.org/en-US/docs/Mozilla/Thunderbird/Hidden_prefs