Fix syntax error

Author: pierredup

messenger.rst

@@ -2097,7 +2097,7 @@ is it up or down. It is possible to do so by dispatching a
             $this->bus->dispatch(new PingWebhookMessage('GET', 'https://example.com/status'));
 
             // Ping, but does not throw on 3xx/4xx/5xx
-            $this->bus->dispatch(new PingWebhookMessage('GET', 'https://example.com/status', throw: false);
+            $this->bus->dispatch(new PingWebhookMessage('GET', 'https://example.com/status', throw: false));
 
             // Any valid HttpClientInterface option can be used
             $this->bus->dispatch(new PingWebhookMessage('POST', 'https://example.com/status', [