Fix -version output not to print spurious lines

main.go

@@ -113,9 +113,11 @@ func main() {
 	if *versionFlag {
 		if Version != "" {
 			fmt.Println(Version)
+			return
 		}
 		if buildInfo, ok := debug.ReadBuildInfo(); ok {
 			fmt.Println(buildInfo.Main.Version)
+			return
 		}
 		fmt.Println("(unknown)")
 		return