mod_admin_blocklist: Fix traceback due to misplaced parenthesis
get_jids_with_role() throws an exception when 'host' is nil since
Prosody trunk rev 7ca5645f46cd
local count_registering = module:measure("user_registering", "rate");
local count_registered = module:measure("user_registered", "rate");
module:hook("user-registering", function ()
count_registering();
end);
module:hook("user-registered", function ()
count_registered();
end);