Update errdefs to 0.3.0

Uses the new github.com/containerd/errdefs/pkg module which is intended
to hold less stable utility functions separately from the stable
github.com/containerd/errdefs error types.

Includes temporary update to hcsshim until a release is cut there

Signed-off-by: Derek McGowan <derek@mcg.dev>

vendor/github.com/Microsoft/hcsshim/internal/hns/hnsendpoint.go

@@ -29,7 +29,7 @@ const (
 )
 
 func (es EndpointState) String() string {
-	return [...]string{"Uninitialized", "Attached", "AttachedSharing", "Detached", "Degraded", "Destroyed"}[es]
+	return [...]string{"Uninitialized", "Created", "Attached", "AttachedSharing", "Detached", "Degraded", "Destroyed"}[es]
 }
 
 // HNSEndpoint represents a network endpoint in HNS

vendor/github.com/Microsoft/hcsshim/internal/oc/errors.go

@@ -6,7 +6,7 @@ import (
 	"net"
 	"os"
 
-	"github.com/containerd/errdefs"
+	"github.com/containerd/containerd/errdefs"
 	"google.golang.org/grpc/codes"
 	"google.golang.org/grpc/status"
 )