Update libera webchat client URL

Libera have made a webchat client available. This change builds on #12127.

Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Signed-off-by: Jonathon Fernyhough <jonathon@m2x.dev>
Closes #12251

.github/ISSUE_TEMPLATE/config.yml

@@ -7,5 +7,5 @@ contact_links:
     url: https://lists.freebsd.org/mailman/listinfo/freebsd-fs
     about: Get community support for OpenZFS on FreeBSD
   - name: OpenZFS on IRC
-    url: https://kiwiirc.com/nextclient/irc.libera.chat/openzfs
+    url: https://web.libera.chat/#openzfs
     about: Use IRC to get community support for OpenZFS