Optimization and refactoring of Go code with channels

It is necessary to improve the program structure by removing potential locking issues and making it more readable.

func main() {
    dataCh := make(chan int)

    for val := range dataCh {
        fmt.Println(val)
    }

    go func() {
        dataCh <- 1
        dataCh <- 2
        dataCh <- 3
    }()
}