io/ioutil has already been deprecated in golang 1.16, so replace all ioutil with io and os

test/e2e_node/device_manager_test.go

@@ -19,7 +19,6 @@ package e2enode
 import (
 	"context"
 	"fmt"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 	"regexp"
@@ -306,8 +305,8 @@ func rewriteCheckpointAsV1(dir, name string) error {
 
 	// TODO: why `checkpointManager.CreateCheckpoint(name, cpV1)` doesn't seem to work?
 	ckPath := filepath.Join(dir, name)
-	ioutil.WriteFile(filepath.Join("/tmp", name), blob, 0600)
-	return ioutil.WriteFile(ckPath, blob, 0600)
+	os.WriteFile(filepath.Join("/tmp", name), blob, 0600)
+	return os.WriteFile(ckPath, blob, 0600)
 }
 
 func convertPodDeviceEntriesToV1(entries []checkpoint.PodDevicesEntry) []checkpoint.PodDevicesEntryV1 {