Don't direct to freenode in issue template

While Libera doesn't yet have a webchat client, we should at least
direct them to the right network. Once a webchat client is available,
we can direct them to it.

Reviewed-by: Brian Behlendorf <behlendorf1@llnl.gov>
Reviewed-by: Matthew Ahrens <mahrens@delphix.com>
Signed-off-by: Paul Dagnelie <pcd@delphix.com>
Closes #12127

.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://webchat.freenode.net/#openzfs
+    url: https://kiwiirc.com/nextclient/irc.libera.chat/openzfs
     about: Use IRC to get community support for OpenZFS