Apply fixes from StyleCI

Author: StyleCIBot

src/Client/OpenBanking.php

@@ -26,7 +26,7 @@ final class OpenBanking extends OAuth2
     protected string $tokenUrl = '';
 
     /**
-     * @var null|string
+     * @var string|null
      */
     protected ?string $scope = null;
 
@@ -198,4 +198,4 @@ public function decodeIdToken(string $idToken): array
         $decoded = json_decode($payloadJson ?: '', true);
         return is_array($decoded) ? $decoded : [];
     }
-}
+}