Refine exception message

Co-authored-by: Karel <[email protected]>

src/Security/Http/Firewall/RefreshAccessTokenListener.php

@@ -47,6 +47,6 @@ protected function refreshToken(OAuthToken $token): OAuthToken
             }
         }
 
-        throw new \RuntimeException('Unsupported authenticator, expecting OAuthAuthenticator, got ' . get_debug_type($this->authenticator));
+        throw new \RuntimeException('Unsupported authenticator, expecting OAuthAuthenticator, got ' . get_class($this->authenticator));
     }
 }