jicofo: fix healthcheck

Fixes: #929

jicofo/rootfs/defaults/jicofo.conf

@@ -122,7 +122,7 @@ jicofo {
         domain = "{{ .Env.XMPP_AUTH_DOMAIN }}"
         username = "{{ .Env.JICOFO_AUTH_USER }}"
         password = "{{ .Env.JICOFO_AUTH_PASSWORD }}"  
-        conference-muc-jid = "{{ first (splitList "." .Env.XMPP_MUC_DOMAIN) }}"
+        conference-muc-jid = "{{ .Env.XMPP_MUC_DOMAIN }}"
         disable-certificate-verification = true
       }
     }