kubelet: Make service environment variables optional

pkg/kubelet/config/http_test.go

@@ -129,6 +129,7 @@ func TestExtractPodsFromHTTP(t *testing.T) {
 	nodeName := "different-value"
 
 	grace := int64(30)
+	enableServiceLinks := api.DefaultEnableServiceLinks
 	var testCases = []struct {
 		desc     string
 		pods     runtime.Object
@@ -173,6 +174,7 @@ func TestExtractPodsFromHTTP(t *testing.T) {
 						SecurityContext:               &v1.PodSecurityContext{},
 						TerminationGracePeriodSeconds: &grace,
 						SchedulerName:                 api.DefaultSchedulerName,
+						EnableServiceLinks:            &enableServiceLinks,
 
 						Containers: []v1.Container{{
 							Name:  "1",
@@ -244,6 +246,7 @@ func TestExtractPodsFromHTTP(t *testing.T) {
 						TerminationGracePeriodSeconds: &grace,
 						SecurityContext:               &v1.PodSecurityContext{},
 						SchedulerName:                 api.DefaultSchedulerName,
+						EnableServiceLinks:            &enableServiceLinks,
 
 						Containers: []v1.Container{{
 							Name:  "1",
@@ -272,6 +275,7 @@ func TestExtractPodsFromHTTP(t *testing.T) {
 						TerminationGracePeriodSeconds: &grace,
 						SecurityContext:               &v1.PodSecurityContext{},
 						SchedulerName:                 api.DefaultSchedulerName,
+						EnableServiceLinks:            &enableServiceLinks,
 
 						Containers: []v1.Container{{
 							Name:  "2",