Fix race condition in Matterbridge sender

sender_worker.go

@@ -121,9 +121,11 @@ type MatterbridgeMessage struct {
 func SendToMatterbridge(events <-chan GenericMessage, s SatelNameGetter, config AppConfig, wg *sync.WaitGroup, logger *log.Logger, tpl *template.Template) <-chan GenericMessage {
 	returnEvents := make(chan GenericMessage)
 
-	go func() {
 	wg.Add(1)
+	go func() {
 		defer wg.Done()
+		defer close(returnEvents)
+
 		for e := range events {
 			returnEvents <- e
 			for _, matterbridgeConfig := range config.Matterbridge {
@@ -145,7 +147,6 @@ func SendToMatterbridge(events <-chan GenericMessage, s SatelNameGetter, config
 				logger.Print("Notified via Matterbridge with result ", res.StatusCode)
 			}
 		}
-		close(returnEvents)
 	}()
 
 	return returnEvents