fix: fix string racing

cmd/gocq/login.go

@@ -221,26 +221,23 @@ func loginResponseProcessor(res *client.LoginResponse) error {
 func getTicket(u string) (str string) {
 	id := utils.RandomString(8)
 	log.Warnf("请前往该地址验证 -> %v <- 或输入手动抓取的 ticket：（Enter 提交）", strings.ReplaceAll(u, "https://ssl.captcha.qq.com/template/wireless_mqq_captcha.html?", fmt.Sprintf("https://captcha.go-cqhttp.org/captcha?id=%v&", id)))
-	manual := make(chan string)
+	manual := make(chan string, 1)
 	go func() {
-		str = readLine()
+		manual <- readLine()
-		manual <- str
 	}()
 	ticker := time.NewTicker(time.Second)
+	defer ticker.Stop()
 	for count := 120; count > 0; count-- {
 		select {
 		case <-ticker.C:
 			str = fetchCaptcha(id)
 			if str != "" {
-				ticker.Stop()
 				return
 			}
-		case <-manual:
+		case str = <-manual:
-			ticker.Stop()
 			return
 		}
 	}
-	ticker.Stop()
 	log.Warnf("验证超时")
 	return ""
 }