func (s *Once) Start(_ context.Context) <-chan struct{} {
	ch := make(chan struct{})
	go func() {
		ch <- struct{}{}
		close(ch)
	}()
	return ch
}
Start returns closed channel with a single element to prevent any repeats
package strategy
import (
	"context"
	"time"
)
type Interface interface {
	Start(ctx context.Context) <-chan struct{}
}
type Once struct{}