feat: use bytes.NewReader(nil) instead of stdin in genyaml

cmd/genyaml/gen_kubectl_yaml.go

@@ -17,6 +17,7 @@ limitations under the License.
 package main
 
 import (
+	"bytes"
 	"fmt"
 	"io/ioutil"
 	"os"
@@ -64,8 +65,7 @@ func main() {
 	// Set environment variables used by kubectl so the output is consistent,
 	// regardless of where we run.
 	os.Setenv("HOME", "/home/username")
-	// TODO os.Stdin should really be something like ioutil.Discard, but a Reader
-	kubectl := cmd.NewKubectlCommand(os.Stdin, ioutil.Discard, ioutil.Discard)
+	kubectl := cmd.NewKubectlCommand(bytes.NewReader(nil), ioutil.Discard, ioutil.Discard)
 	genYaml(kubectl, "", outDir)
 	for _, c := range kubectl.Commands() {
 		genYaml(c, "kubectl", outDir)