[issue:4537] Fix doc error of producer options (#4571)

Signed-off-by: Nxiaolong.ran <ranxiaolong716@gmail.com>

site2/docs/client-libraries-go.md

@@ -193,7 +193,7 @@ func main() {
         producer.SendAsync(ctx, asyncMsg, func(msg pulsar.ProducerMessage, err error) {
             if err != nil { log.Fatal(err) }
 
-            fmt.Printf("Message %s succesfully published", msg.ID())
+            fmt.Printf("the %s successfully published", string(msg.Payload))
         })
     }
 }