fix: resolve lint issues in webhook e2e tests and consumer webhook

- Remove unused messageSubstrings variadic parameter from expectAdmissionDenied
- Add nolint:dupl to warn-on-missing It blocks (structurally similar but different YAML)
- Fix gofmt trailing newline in consumer_webhook.go

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

Author: AlinsRan

internal/webhook/v1/consumer_webhook.go

@@ -239,4 +239,3 @@ func (v *ConsumerCustomValidator) extractCredentialKey(ctx context.Context, cons
 	}
 	return cfg.Key, nil
 }
-

test/e2e/webhook/apisixconsumer.go

@@ -47,7 +47,7 @@ var _ = Describe("Test ApisixConsumer Webhook", Label("webhook"), func() {
 		time.Sleep(5 * time.Second)
 	})
 
-	It("should warn on missing authentication secrets", func() {
+	It("should warn on missing authentication secrets", func() { //nolint:dupl
 		missingSecret := "missing-basic-secret"
 		consumerName := "webhook-apisixconsumer"
 		consumerYAML := `

test/e2e/webhook/apisixroute.go

@@ -46,7 +46,7 @@ var _ = Describe("Test ApisixRoute Webhook", Label("webhook"), func() {
 		time.Sleep(5 * time.Second)
 	})
 
-	It("should warn on missing service references", func() {
+	It("should warn on missing service references", func() { //nolint:dupl
 		missingService := "missing-backend"
 		routeName := "webhook-apisixroute"
 		routeYAML := `

test/e2e/webhook/helpers.go

@@ -236,12 +236,9 @@ spec:
 	Expect(output).NotTo(ContainSubstring(missingBackendWarning))
 }
 
-func expectAdmissionDenied(s *scaffold.Scaffold, resourceType, resourceName string, err error, messageSubstrings ...string) {
+func expectAdmissionDenied(s *scaffold.Scaffold, resourceType, resourceName string, err error) {
 	Expect(err).To(HaveOccurred(), "expecting admission rejection")
 	Expect(err.Error()).To(ContainSubstring("denied the request"))
-	for _, substring := range messageSubstrings {
-		Expect(err.Error()).To(ContainSubstring(substring))
-	}
 
 	_, getErr := s.GetOutputFromString(resourceType, resourceName, "-o", "yaml")
 	Expect(getErr).To(HaveOccurred(), fmt.Sprintf("resource %s/%s should not exist after admission rejection", resourceType, resourceName))