Update go version, modules and remove ioutil

internal/file/file.go

@@ -19,7 +19,7 @@ package file
 import (
 	"crypto/sha1" // #nosec
 	"encoding/hex"
-	"io/ioutil"
+	"os"
 
 	"k8s.io/klog/v2"
 )
@@ -27,7 +27,7 @@ import (
 // SHA1 returns the SHA1 of a file.
 func SHA1(filename string) string {
 	hasher := sha1.New() // #nosec
-	s, err := ioutil.ReadFile(filename)
+	s, err := os.ReadFile(filename)
 	if err != nil {
 		klog.ErrorS(err, "Error reading file", "path", filename)
 		return ""

internal/file/file_test.go

@@ -17,7 +17,7 @@ limitations under the License.
 package file
 
 import (
-	"io/ioutil"
+	"os"
 	"testing"
 )
 
@@ -31,7 +31,7 @@ func TestSHA1(t *testing.T) {
 	}
 
 	for _, test := range tests {
-		f, err := ioutil.TempFile("", "sha-test")
+		f, err := os.CreateTemp("", "sha-test")
 		if err != nil {
 			t.Fatal(err)
 		}