fix invalid managed-by label value

api/krusty/kustomizer.go

@@ -85,7 +85,7 @@ func (b *Kustomizer) Run(path string) (resmap.ResMap, error) {
 		t := builtins.LabelTransformerPlugin{
 			Labels: map[string]string{
 				konfig.ManagedbyLabelKey: fmt.Sprintf(
-					"kustomize-%s", provenance.GetProvenance().Version)},
+					"kustomize-%s", provenance.GetProvenance().Semver())},
 			FieldSpecs: []types.FieldSpec{{
 				Path:               "metadata/labels",
 				CreateIfNotPresent: true,

api/provenance/provenance.go

@@ -6,6 +6,7 @@ package provenance
 import (
 	"fmt"
 	"runtime"
+	"strings"
 )
 
 var (
@@ -57,3 +58,11 @@ func (v Provenance) Short() string {
 			BuildDate: v.BuildDate,
 		})
 }
+
+// Semver returns the semantic version of kustomize.
+// kustomize version is set in format "kustomize/vX.X.X" in every release.
+// X.X.X is a semver. If the version string is not in this format,
+// return the original version string
+func (v Provenance) Semver() string {
+	return strings.TrimPrefix(v.Version, "kustomize/")
+}