delete io/ioutil package. (#5955)

Signed-off-by: yanggang <gang.yang@daocloud.io>

pkg/plugin/clientmgmt/process/registry_test.go

@@ -5,7 +5,7 @@ Licensed under the Apache License, Version 2.0 (the "License");
 you may not use this file except in compliance with the License.
 You may obtain a copy of the License at
 
-    http://www.apache.org/licenses/LICENSE-2.0
+	http://www.apache.org/licenses/LICENSE-2.0
 
 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
@@ -16,6 +16,7 @@ limitations under the License.
 package process
 
 import (
+	"io/fs"
 	"os"
 	"sort"
 	"testing"
@@ -43,7 +44,7 @@ func TestNewRegistry(t *testing.T) {
 }
 
 type fakeFileInfo struct {
-	os.FileInfo
+	fs.FileInfo
 	mode os.FileMode
 }