fix: do not add

Author: cuiweixie

colly.go

@@ -906,8 +906,8 @@ func (c *Collector) checkRobots(u *url.URL) error {
 func (c *Collector) String() string {
 	return fmt.Sprintf(
 		"Requests made: %d (%d responses) | Callbacks: OnRequest: %d, OnHTML: %d, OnResponse: %d, OnError: %d",
-		c.requestCount.Add(1),
-		c.responseCount.Add(1),
+		c.requestCount.Load(),
+		c.responseCount.Load(),
 		len(c.requestCallbacks),
 		len(c.htmlCallbacks),
 		len(c.responseCallbacks),