Unnecessary check in gracefulShutdown

[mojixcoder]

In StartConfig.start:

if sc.GracefulTimeout >= 0 {
	gCtx, cancel := stdContext.WithCancel(ctx) // end goroutine when Serve returns early
	defer cancel()
	go gracefulShutdown(gCtx, &sc, &server, logger)
}

and inside gracefulShutdown method:

timeout := sc.GracefulTimeout
if timeout == 0 {
	timeout = 10 * time.Second
}

this timeout == 0 never reaches since it is checked before, we should either remove sc.GracefulTimeout >= 0 or if timeout == 0.