fix $sub typo in SUBSCRIBE_AMQP

kamailio/presence-role.cfg

@@ -153,7 +153,7 @@ route[HANDLE_NEW_SUBSCRIBE]
 route[SUBSCRIBE_AMQP]
 {
     $var(rk) = "subscribe." + $(subs(to_domain){kz.encode}) + "." + $(subs(to_user){kz.encode});
-    $var(amqp_payload_request) = $_s({"Event-Category" : "presence", "Event-Name" : "subscription", "Event-Package" : "$hdr(event)", "Expires" : $sub(expires), "Queue" : "BLF-MY_HOSTNAME", "Server-ID" : "BLF-MY_HOSTNAME" , "Contact" : "$(ct{s.escape.common}{s.replace,\','}{s.replace,$$,})", "Call-ID" : "$ci", "From" : "$fu", "User" : "$subs(uri)", "User-Agent" : "$(ua{s.escape.common}{s.replace,\','}{s.replace,$$,})" });
+    $var(amqp_payload_request) = $_s({"Event-Category" : "presence", "Event-Name" : "subscription", "Event-Package" : "$hdr(event)", "Expires" : $subs(expires), "Queue" : "BLF-MY_HOSTNAME", "Server-ID" : "BLF-MY_HOSTNAME" , "Contact" : "$(ct{s.escape.common}{s.replace,\','}{s.replace,$$,})", "Call-ID" : "$ci", "From" : "$fu", "User" : "$subs(uri)", "User-Agent" : "$(ua{s.escape.common}{s.replace,\','}{s.replace,$$,})" });
     kazoo_publish("omnipresence", "$var(rk)", $var(amqp_payload_request));
 }