[GE-2026] add button for the sponsor link

Author: deniger

content/events/2026-geneva/welcome.md

@@ -55,14 +55,20 @@ Description = "DevOpsDays Geneva 2026"
           <a class="btn btn-primary btn-block"
             style="margin-top: 15px; margin-bottom: 15px; background-color: #ED1C24; border-color: #ED1C24;"
             href="/events/2026-geneva/registration">
-            <i class="fa fa-ticket fa-lg"></i>&nbsp;&nbsp;&nbsp;Register to attend the conference!
+            <i class="fa fa-ticket fa-lg"></i>&nbsp;&nbsp;&nbsp;Register to attend the conference
           </a>
         </div>
         <div class="d-flex p-2">
           <a class="btn btn-primary btn-block"
             style="margin-top: 15px; margin-bottom: 15px; background-color: #ED1C24; border-color: #ED1C24;"
             href="/events/2026-geneva/propose">
-            <i class="fa fa-person-chalkboard fa-lg"></i>&nbsp;&nbsp;&nbsp;Propose a talk!</a>
+            <i class="fa fa-person-chalkboard fa-lg"></i>&nbsp;&nbsp;&nbsp;Propose a talk</a>
+        </div>
+        <div class="d-flex p-2">
+          <a class="btn btn-primary btn-block"
+            style="margin-top: 15px; margin-bottom: 15px; background-color: #ED1C24; border-color: #ED1C24;"
+            href="/events/2026-geneva/sponsor">
+            <i class="fa fa-handshake fa-lg"></i>&nbsp;&nbsp;&nbsp;Sponsor the conference</a>
         </div>
     </div>
 </div>