do not use ioutil (#9206)

config/toml.go

@@ -3,7 +3,7 @@ package config
 import (
 	"bytes"
 	"fmt"
-	"io/ioutil"
+	"os"
 	"path/filepath"
 	"strings"
 	"text/template"
@@ -535,7 +535,7 @@ func ResetTestRoot(testName string) *Config {
 
 func ResetTestRootWithChainID(testName string, chainID string) *Config {
 	// create a unique, concurrency-safe test directory under os.TempDir()
-	rootDir, err := ioutil.TempDir("", fmt.Sprintf("%s-%s_", chainID, testName))
+	rootDir, err := os.MkdirTemp("", fmt.Sprintf("%s-%s_", chainID, testName))
 	if err != nil {
 		panic(err)
 	}

config/toml_test.go

@@ -1,7 +1,6 @@
 package config
 
 import (
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"strings"
@@ -23,7 +22,7 @@ func TestEnsureRoot(t *testing.T) {
 	require := require.New(t)
 
 	// setup temp dir for test
-	tmpDir, err := ioutil.TempDir("", "config-test")
+	tmpDir, err := os.MkdirTemp("", "config-test")
 	require.Nil(err)
 	defer os.RemoveAll(tmpDir)
 
@@ -31,7 +30,7 @@ func TestEnsureRoot(t *testing.T) {
 	EnsureRoot(tmpDir)
 
 	// make sure config is set properly
-	data, err := ioutil.ReadFile(filepath.Join(tmpDir, defaultConfigFilePath))
+	data, err := os.ReadFile(filepath.Join(tmpDir, defaultConfigFilePath))
 	require.Nil(err)
 
 	if !checkConfig(string(data)) {
@@ -52,7 +51,7 @@ func TestEnsureTestRoot(t *testing.T) {
 	rootDir := cfg.RootDir
 
 	// make sure config is set properly
-	data, err := ioutil.ReadFile(filepath.Join(rootDir, defaultConfigFilePath))
+	data, err := os.ReadFile(filepath.Join(rootDir, defaultConfigFilePath))
 	require.Nil(err)
 
 	if !checkConfig(string(data)) {