Update link to source repo in uhh-cms

Author: mschrode

index.html

@@ -95,7 +95,7 @@ <h2 data-i18n="about.title"></h2>
           <div id="js-start-event" class="start-btn">
             <p  data-i18n="about.start"></p>
           </div>
-          <p><span data-i18n="about.github"></span><a class="btn btn-primary" role="button" href="https://github.com/haddadanas/Masterclass_UHH" target="_blank" rel="noopener noreferrer"><i class="fab fa-github"></i>&nbsp;Masterclass_UHH @ stable</a></p>
+          <p><span data-i18n="about.github"></span><a class="btn btn-primary" role="button" href="https://github.com/uhh-cms-tutorials/masterclasses" target="_blank" rel="noopener noreferrer"><i class="fab fa-github"></i>&nbsp;uhh-cms-tutorials/masterclasses</a></p>
           <p><span data-i18n="about.sponsors"></span><br><a href="https://www.uni-hamburg.de/" target="_blank" rel="noopener noreferrer"><img src="assets/img/up-uhh-logo-u-2010-u-png.png" loading="lazy" alt="UHH Logo" height="70px" id="uhh-light" title="Universität Hamburg" data-bs-toggle="tooltip"><img src="assets/img/uhh-logo-2010-farbnegativ-rgb.png" loading="lazy" alt="UHH Logo" height="70px" id="uhh-dark" title="Universität Hamburg" data-bs-toggle="tooltip"></a><a href="https://www.desy.de/" target="_blank" rel="noopener noreferrer"><img src="https://pr.desy.de/common/desy_logo_3c_web.svg" loading="lazy" title="Deutsches Elektronen-Synchrotron, Standort Hamburg" alt="DESY Logo" height="70" data-bs-toggle="tooltip"></a><br><span class="img-remark">Logos: (<span data-i18n="about.left"></span>) &copy; UHH (<span data-i18n="about.right"></span>) &copy; DESY</span></p>
 
         </div>