@Override
    protected Action getExecuteAction(@Nonnull final SessionData data) {
        //Do nothing since there are no stages
        return null;
    }
Command that allows to retrieve the number of idle users. Idle users are those that are online, but not active.
Active users are those users that have sent an available presence.

@author Guus der Kinderen, guus@goodbytes.nl
@see <a href="https://xmpp.org/extensions/xep-0133.html#get-idle-users-num">XEP-0133 Service Administration: Get Number of Idle Users</a>
xmppserver/src/main/java/org/jivesoftware/openfire/commands/admin/GetNumberIdleUsers.java