Update worker.go

fix: Ack should be an the end of loop.

go/worker.go

@@ -56,11 +56,11 @@ func main() {
 	go func() {
 		for d := range msgs {
 			log.Printf("Received a message: %s", d.Body)
-			d.Ack(false)
 			dot_count := bytes.Count(d.Body, []byte("."))
 			t := time.Duration(dot_count)
 			time.Sleep(t * time.Second)
 			log.Printf("Done")
+			d.Ack(false)
 		}
 	}()