Remove gogoproto.stdtime

This commit removes gogoproto.stdtime, since it is not supported by
Google's official toolchain
(see https://github.com/containerd/containerd/issues/6564).

Signed-off-by: Kazuyoshi Kato <katokazu@amazon.com>

runtime/v2/shim/publisher.go

@@ -116,7 +116,7 @@ func (l *RemoteEventsPublisher) Publish(ctx context.Context, topic string, event
 	}
 	i := &item{
 		ev: &v1.Envelope{
-			Timestamp: time.Now(),
+			Timestamp: protobuf.ToTimestamp(time.Now()),
 			Namespace: ns,
 			Topic:     topic,
 			Event:     any,

runtime/v2/shim/shim.go

@@ -34,6 +34,7 @@ import (
 	"github.com/containerd/containerd/namespaces"
 	"github.com/containerd/containerd/pkg/shutdown"
 	"github.com/containerd/containerd/plugin"
+	"github.com/containerd/containerd/protobuf"
 	shimapi "github.com/containerd/containerd/runtime/v2/task"
 	"github.com/containerd/containerd/version"
 	"github.com/containerd/ttrpc"
@@ -218,7 +219,7 @@ func (stm shimToManager) Stop(ctx context.Context, id string) (StopStatus, error
 	return StopStatus{
 		Pid:        int(dr.Pid),
 		ExitStatus: int(dr.ExitStatus),
-		ExitedAt:   dr.ExitedAt,
+		ExitedAt:   protobuf.FromTimestamp(dr.ExitedAt),
 	}, nil
 }
 
@@ -314,7 +315,7 @@ func run(ctx context.Context, manager Manager, initFunc Init, name string, confi
 		data, err := proto.Marshal(&shimapi.DeleteResponse{
 			Pid:        uint32(ss.Pid),
 			ExitStatus: uint32(ss.ExitStatus),
-			ExitedAt:   ss.ExitedAt,
+			ExitedAt:   protobuf.ToTimestamp(ss.ExitedAt),
 		})
 		if err != nil {
 			return err