nydus: fix missing imports

Signed-off-by: Justin Chadwell <me@jedevc.com>

Author: jedevc

cache/compression_nydus.go

@@ -10,6 +10,7 @@ import (
 
 	"github.com/containerd/containerd/content"
 	"github.com/containerd/containerd/errdefs"
+	"github.com/containerd/containerd/labels"
 	"github.com/moby/buildkit/cache/config"
 	"github.com/moby/buildkit/session"
 	"github.com/moby/buildkit/util/compression"

util/compression/nydus.go

@@ -9,6 +9,7 @@ import (
 
 	"github.com/containerd/containerd/content"
 	"github.com/containerd/containerd/images"
+	"github.com/containerd/containerd/labels"
 	digest "github.com/opencontainers/go-digest"
 	ocispecs "github.com/opencontainers/image-spec/specs-go/v1"
 	"github.com/pkg/errors"