fix registration status provider on null response

src/State/Provider/OnlineRegistration/RegistrationStatusProvider.php

@@ -52,10 +52,9 @@ class RegistrationStatusProvider implements ProviderInterface
             'your_registration_file_has_been_validated' => RegistrationStatusEnum::ACCEPTED,
             'you_have_been_placed_on_the_waiting_list' => RegistrationStatusEnum::PENDING,
             'your_application_has_been_refused' => RegistrationStatusEnum::DENIED,
-            null => null,
         ];
 
-        $status = isset($response['status']) ? $statusMap[$response['status']] : null;
+        $status = isset($response['status']) && !empty($response['status']) ? $statusMap[$response['status']] : null;
 
         $registrationStatus = new RegistrationStatus();
         $registrationStatus->setAccessId($currentAccess->getId());