fix: [stix 1/2 import] Adding misp event json data within the 'Event' field if it is not already in

app/Model/Event.php

@@ -5844,6 +5844,9 @@ class Event extends AppModel
         if (trim($result) == '1') {
             $data = file_get_contents($output_path);
             $data = json_decode($data, true);
+            if (empty($data['Event'])) {
+                $data = array('Event' => $data);
+            }
             unlink($output_path);
             $created_id = false;
             $validationIssues = false;