remove windows service not used global variable

Signed-off-by: gy95 <1015105054@qq.com>

pkg/windows/service/service.go

@@ -29,10 +29,6 @@ import (
 	"golang.org/x/sys/windows/svc"
 )
 
-var (
-	service *handler
-)
-
 type handler struct {
 	tosvc   chan bool
 	fromsvc chan error
@@ -47,7 +43,6 @@ func InitService(serviceName string) error {
 		fromsvc: make(chan error),
 	}
 
-	service = h
 	var err error
 	go func() {
 		err = svc.Run(serviceName, h)