ovsconf 2025: Point to the link correction email.

Signed-off-by: Ilya Maximets <i.maximets@ovn.org>

Author: igsilya

_includes/side-widgets.html

@@ -5,7 +5,7 @@
   <div class="widget-body">
     <ul>
       <li>
-        <a href=https://mail.openvswitch.org/pipermail/ovs-announce/2025-July/000371.html>July 31 2025: OVS+OVN '25: Call for Participation</a>
+        <a href=https://mail.openvswitch.org/pipermail/ovs-announce/2025-July/000372.html>July 31 2025: OVS+OVN '25: Call for Participation</a>
       </li>
       <li>
         <a href=https://mail.openvswitch.org/pipermail/ovs-announce/2025-June/000368.html>Jun 02 2025: Open vSwitch 3.5.1, 3.4.3 and 3.3.5 are available</a>