[11.x] Update config/mail.php with supported configuration (#6506)

Signed-off-by: Mior Muhammad Zaki <crynobone@gmail.com>

config/mail.php

@@ -39,10 +39,10 @@ return [
 
         'smtp' => [
             'transport' => 'smtp',
+            'scheme' => env('MAIL_SCHEME'),
             'url' => env('MAIL_URL'),
             'host' => env('MAIL_HOST', '127.0.0.1'),
             'port' => env('MAIL_PORT', 2525),
-            'encryption' => env('MAIL_ENCRYPTION', 'tls'),
             'username' => env('MAIL_USERNAME'),
             'password' => env('MAIL_PASSWORD'),
             'timeout' => null,