Fix SetFeatureGateDuringTest handling of Parallel tests

Stop using defer as parallel subtest will might result in main test
finishing before subtest.

Fatal when same flag is set twice.

Kubernetes-commit: 9fcf279e2b91e7549190a433373f256fb5aebe85

test/integration/fieldselector_test.go

@@ -699,13 +699,13 @@ func TestFieldSelectorDisablement(t *testing.T) {
 
 	crd := selectableFieldFixture.DeepCopy()
 	// Write a field that uses the feature while the feature gate is enabled
-	func() {
+	t.Run("CustomResourceFieldSelectors", func(t *testing.T) {
 		defer featuregatetesting.SetFeatureGateDuringTest(t, utilfeature.DefaultFeatureGate, apiextensionsfeatures.CustomResourceFieldSelectors, true)()
 		crd, err = fixtures.CreateNewV1CustomResourceDefinition(crd, apiExtensionClient, dynamicClient)
 		if err != nil {
 			t.Fatal(err)
 		}
-	}()
+	})
 
 	// Now that the feature gate is disabled again, update the CRD to trigger an openAPI update
 	crd, err = apiExtensionClient.ApiextensionsV1().CustomResourceDefinitions().Get(ctx, crd.Name, metav1.GetOptions{})