TUN-8052: Update go to 1.21.5

Also update golang.org/x/net and google.golang.org/grpc to fix vulnerabilities,
although cloudflared is using them in a way that is not exposed to those risks

vendor/github.com/grpc-ecosystem/grpc-gateway/v2/runtime/marshal_proto.go

@@ -1,10 +1,8 @@
 package runtime
 
 import (
-	"io"
-
 	"errors"
-	"io/ioutil"
+	"io"
 
 	"google.golang.org/protobuf/proto"
 )
@@ -38,7 +36,7 @@ func (*ProtoMarshaller) Unmarshal(data []byte, value interface{}) error {
 // NewDecoder returns a Decoder which reads proto stream from "reader".
 func (marshaller *ProtoMarshaller) NewDecoder(reader io.Reader) Decoder {
 	return DecoderFunc(func(value interface{}) error {
-		buffer, err := ioutil.ReadAll(reader)
+		buffer, err := io.ReadAll(reader)
 		if err != nil {
 			return err
 		}
@@ -53,8 +51,7 @@ func (marshaller *ProtoMarshaller) NewEncoder(writer io.Writer) Encoder {
 		if err != nil {
 			return err
 		}
-		_, err = writer.Write(buffer)
-		if err != nil {
+		if _, err := writer.Write(buffer); err != nil {
 			return err
 		}