Chore: remove deprecated ioutil

dns/doh.go

@@ -3,7 +3,7 @@ package dns
 import (
 	"bytes"
 	"context"
-	"io/ioutil"
+	"io"
 	"net"
 	"net/http"
 
@@ -68,7 +68,7 @@ func (dc *dohClient) doRequest(req *http.Request) (msg *D.Msg, err error) {
 	}
 	defer resp.Body.Close()
 
-	buf, err := ioutil.ReadAll(resp.Body)
+	buf, err := io.ReadAll(resp.Body)
 	if err != nil {
 		return nil, err
 	}