Fixing push notificaiton (#5394)

app/notification.go

@@ -536,6 +536,7 @@ func sendToPushProxy(msg model.PushNotification) *model.AppError {
 
 	tr := &http.Transport{
 		TLSClientConfig:   &tls.Config{InsecureSkipVerify: *utils.Cfg.ServiceSettings.EnableInsecureOutgoingConnections},
+		DisableKeepAlives: true,
 	}
 	httpClient := &http.Client{Transport: tr}
 	request, _ := http.NewRequest("POST", *utils.Cfg.EmailSettings.PushNotificationServer+model.API_URL_SUFFIX_V1+"/send_push", strings.NewReader(msg.ToJson()))