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/v1/linux/runtime.go

@@ -463,7 +463,7 @@ func (r *Runtime) cleanupAfterDeadShim(ctx context.Context, bundle *bundle, ns,
 		ID:          id,
 		Pid:         uint32(pid),
 		ExitStatus:  128 + uint32(unix.SIGKILL),
-		ExitedAt:    exitedAt,
+		ExitedAt:    protobuf.ToTimestamp(exitedAt),
 	})
 
 	r.tasks.Delete(ctx, id)
@@ -479,7 +479,7 @@ func (r *Runtime) cleanupAfterDeadShim(ctx context.Context, bundle *bundle, ns,
 		ContainerID: id,
 		Pid:         uint32(pid),
 		ExitStatus:  128 + uint32(unix.SIGKILL),
-		ExitedAt:    exitedAt,
+		ExitedAt:    protobuf.ToTimestamp(exitedAt),
 	})
 
 	return nil