Fix. Params. Added submit_time filter.

Author: svfcode

lib/CleantalkAntispam.php

@@ -49,7 +49,7 @@ public function handle()
         $ct_request->sender_ip       = $sender_ip;
         $ct_request->sender_nickname = $sender_nickname;
         $ct_request->message         = $message;
-        $ct_request->submit_time     = $_SESSION['ct_submit_time'];
+        $ct_request->submit_time     = isset($_SESSION['ct_submit_time']) ? $_SESSION['ct_submit_time'] : null;
         $ct_request->event_token     = isset($_POST['ct_bot_detector_event_token']) ? $_POST['ct_bot_detector_event_token'] : null;
 
         $ct             = new Cleantalk();