Use typeurl package for spec types

Signed-off-by: Michael Crosby <crosbymichael@gmail.com>

linux/bundle.go

@@ -6,7 +6,6 @@ import (
 	"bytes"
 	"context"
 	"io"
-	"io/ioutil"
 	"os"
 	"path/filepath"
 
@@ -82,11 +81,6 @@ func (b *bundle) Connect(ctx context.Context, remote bool) (*client.Client, erro
 	}, opt)
 }
 
-// spec returns the spec written to the bundle
-func (b *bundle) Spec() ([]byte, error) {
-	return ioutil.ReadFile(filepath.Join(b.path, configFilename))
-}
-
 // Delete deletes the bundle from disk
 func (b *bundle) Delete() error {
 	return os.RemoveAll(b.path)