add postmark token

config/services.php

@@ -20,6 +20,10 @@ return [
         'endpoint' => env('MAILGUN_ENDPOINT', 'api.mailgun.net'),
     ],
 
+    'postmark' => [
+        'token' => env('POSTMARK_TOKEN'),
+    ],
+
     'ses' => [
         'key' => env('AWS_ACCESS_KEY_ID'),
         'secret' => env('AWS_SECRET_ACCESS_KEY'),