fix windows slash

tools/goctl/api/gogen/util.go

@@ -22,6 +22,7 @@ func getParentPackage(dir string) (string, error) {
 	if err != nil {
 		return "", err
 	}
+	absDir = strings.ReplaceAll(absDir, `\`, `/`)
 
 	var rootPath string
 	var tempPath = absDir