agent/acs/handler/refresh_credentials_handler.go
func (refreshHandler *refreshCredentialsHandler) sendAcks() {
	for {
		select {
		case ack := <-refreshHandler.ackRequest:
			refreshHandler.ackMessage(ack)
		case <-refreshHandler.ctx.Done():
			return
		}
	}
}
func (refreshHandler *refreshCredentialsHandler) sendAcks() {
	for {
		select {
		case ack := <-refreshHandler.ackRequest:
			refreshHandler.ackMessage(ack)
		case <-refreshHandler.ctx.Done():
			return
		}
	}
}
// sendAcks sends ack requests to ACS