proxying to URL is more flexible

src/WebhooksController.php

@@ -15,7 +15,7 @@ class WebhooksController
     {
         $proxy_host = config('appstore-server-notifications.proxy_host');
         if (!empty($proxy_host)) {
-            ProxyHelperFacade::CreateProxy($request)->toHost($proxy_host, '');
+            ProxyHelperFacade::CreateProxy($request)->->toUrl($proxy_host);
         }
 
         $jobConfigKey = NotificationType::{$request->input('notification_type')}();