use time.NewTimer instead of time.After in Sleep
use time.NewTimer instead of time.After in Sleep

To fix a potential temporary goroutine leak; see the added comment. The
leaked goroutine would eventually stop once the timer is fired, but
until then, the goroutine could be unnecessarily left around.

knq/chromedp,knq/chromedp,chromedp/chromedp,chromedp/chromedp,chromedp/chromedp,knq/chromedp