post-processor/docker-tag: remove decodeconfig usage

post-processor/docker-tag/post-processor_test.go

@@ -2,11 +2,11 @@ package dockertag
 
 import (
 	"bytes"
+	"testing"
+
 	"github.com/mitchellh/packer/builder/docker"
-	"github.com/mitchellh/packer/common"
 	"github.com/mitchellh/packer/packer"
 	"github.com/mitchellh/packer/post-processor/docker-import"
-	"testing"
 )
 
 func testConfig() map[string]interface{} {
@@ -39,9 +39,8 @@ func TestPostProcessor_ImplementsPostProcessor(t *testing.T) {
 func TestPostProcessor_PostProcess(t *testing.T) {
 	driver := &docker.MockDriver{}
 	p := &PostProcessor{Driver: driver}
-	_, err := common.DecodeConfig(&p.config, testConfig())
-	if err != nil {
-		t.Fatalf("err %s", err)
+	if err := p.Configure(testConfig()); err != nil {
+		t.Fatalf("err: %s", err)
 	}
 
 	artifact := &packer.MockArtifact{