Update go.mod and vendor

vendor/github.com/containerd/ttrpc/codec.go

@@ -1,42 +0,0 @@
-/*
-   Copyright The containerd Authors.
-
-   Licensed under the Apache License, Version 2.0 (the "License");
-   you may not use this file except in compliance with the License.
-   You may obtain a copy of the License at
-
-       http://www.apache.org/licenses/LICENSE-2.0
-
-   Unless required by applicable law or agreed to in writing, software
-   distributed under the License is distributed on an "AS IS" BASIS,
-   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-   See the License for the specific language governing permissions and
-   limitations under the License.
-*/
-
-package ttrpc
-
-import (
-	"github.com/gogo/protobuf/proto"
-	"github.com/pkg/errors"
-)
-
-type codec struct{}
-
-func (c codec) Marshal(msg interface{}) ([]byte, error) {
-	switch v := msg.(type) {
-	case proto.Message:
-		return proto.Marshal(v)
-	default:
-		return nil, errors.Errorf("ttrpc: cannot marshal unknown type: %T", msg)
-	}
-}
-
-func (c codec) Unmarshal(p []byte, msg interface{}) error {
-	switch v := msg.(type) {
-	case proto.Message:
-		return proto.Unmarshal(p, v)
-	default:
-		return errors.Errorf("ttrpc: cannot unmarshal into unknown type: %T", msg)
-	}
-}