mod_delegation: use clean_xmlns to remove jabber:client namespace from node: for the same reason as in mod_privilege, `jabber:client` namespace is removed with the clean_xmlns method coming from there. Furthermore, the forwarded <iq> stanza use the `jabber:client` xmlns while the stanza may come from a component with e.g. `jabber:component:accept` xmlns, this can lead to inconsistencies between the <iq> stanza and children (like <error> element).

local hostname = module:get_option_string("sasl_hostname", module.host);

module:hook("stream-features", function(event)
	local features = event.features;
	local mechs = features:get_child("mechanisms", "urn:ietf:params:xml:ns:xmpp-sasl");
	if mechs then
		mechs:tag("hostname", { xmlns = "urn:xmpp:domain-based-name:1" })
			:text(hostname):up();
	end
end);