Update code-generator to v0.26.0

client/vendor/k8s.io/code-generator/cmd/client-gen/generators/generator_for_clientset.go

@@ -108,8 +108,7 @@ type Interface interface {
 `
 
 var clientsetTemplate = `
-// Clientset contains the clients for groups. Each group has exactly one
-// version included in a Clientset.
+// Clientset contains the clients for groups.
 type Clientset struct {
 	*$.DiscoveryClient|raw$
     $range .allGroups$$.LowerCaseGroupGoName$$.Version$ *$.PackageAlias$.$.GroupGoName$$.Version$Client

client/vendor/k8s.io/code-generator/cmd/client-gen/main.go

@@ -34,7 +34,6 @@ func main() {
 
 	// Override defaults.
 	// TODO: move this out of client-gen
-	genericArgs.GoHeaderFilePath = util.BoilerplatePath()
 	genericArgs.OutputPackagePath = "k8s.io/kubernetes/pkg/client/clientset_generated/"
 
 	genericArgs.AddFlags(pflag.CommandLine)