Update default.html

Updated format of Mastodon address

Author: chluehr

_layouts/default.html

@@ -89,7 +89,7 @@ <h4>About the Usergroup</h4>
 We meet regularly (1st tuesday each month) at Co-Up in Berlin, Kreuzberg to talk about PHP, Web-development, OpenSource software and similar topics. Curious? Eager to meet new people and to learn about new technology - or keen on sharing the knowledge gained by preparing a talk yourself? Just drop by at the next meetup!
 			</p>                    </div>
                     <div class="widget span3">
-                        <h4>Mastodon: <a rel="me" href="https://phpc.social/@bephpug">phpc.social/@bephpug</a></h4>
+                        <h4>Mastodon: <a rel="me" href="https://phpc.social/@bephpug">@bephpug@phpc.social</a></h4>
                         <h4>Twitter: <a href="https://twitter.com/bephpug">@bephpug</a></h4>
                     </div>
                     <div class="widget span3">