Move FieldSpec to API.

plugin/someteam.example.com/v1/stringprefixer/StringPrefixer.go

@@ -7,7 +7,6 @@ import (
 	"github.com/pkg/errors"
 	"sigs.k8s.io/kustomize/v3/api/types"
 	"sigs.k8s.io/kustomize/v3/pkg/resmap"
-	"sigs.k8s.io/kustomize/v3/pkg/transformers/config"
 	"sigs.k8s.io/kustomize/v3/plugin/builtin"
 	"sigs.k8s.io/yaml"
 )
@@ -27,10 +26,10 @@ func (p *plugin) makePrefixSuffixPluginConfig(n string) ([]byte, error) {
 	var s struct {
 		Prefix     string
 		Suffix     string
-		FieldSpecs []config.FieldSpec
+		FieldSpecs []types.FieldSpec
 	}
 	s.Prefix = n + "-"
-	s.FieldSpecs = []config.FieldSpec{
+	s.FieldSpecs = []types.FieldSpec{
 		{Path: "metadata/name"},
 	}
 	return yaml.Marshal(s)