m/test/e2e: stop downloading container images

Having tests rely on The Internet isn't great, having tests rely on the
Dockercorp registry is even worse. Instead, let's test everything using
the preseed_test image.

Change-Id: Ib82ce266592e9c6d2f0d4597abcc114c12746b1f
Reviewed-on: https://review.monogon.dev/c/monogon/+/1338
Tested-by: Jenkins CI
Reviewed-by: Lorenz Brun <lorenz@monogon.tech>
diff --git a/metropolis/test/e2e/kubernetes_helpers.go b/metropolis/test/e2e/kubernetes_helpers.go
index 2e53970..dec7363 100644
--- a/metropolis/test/e2e/kubernetes_helpers.go
+++ b/metropolis/test/e2e/kubernetes_helpers.go
@@ -75,9 +75,9 @@
 				Spec: corev1.PodSpec{
 					Containers: []corev1.Container{
 						{
-							Name: "test",
-							// TODO(phab/T793): Build and preseed our own container images
-							Image: "nginx:alpine",
+							Name:            "test",
+							ImagePullPolicy: corev1.PullNever,
+							Image:           "bazel/metropolis/test/e2e/preseedtest:preseedtest_image",
 							ReadinessProbe: &corev1.Probe{
 								ProbeHandler: corev1.ProbeHandler{
 									HTTPGet: &corev1.HTTPGetAction{Port: intstr.FromInt(80)},
@@ -120,8 +120,9 @@
 				Spec: corev1.PodSpec{
 					Containers: []corev1.Container{
 						{
-							Name:  "test",
-							Image: "nginx:alpine",
+							Name:            "test",
+							ImagePullPolicy: corev1.PullNever,
+							Image:           "bazel/metropolis/test/e2e/preseedtest:preseedtest_image",
 							ReadinessProbe: &corev1.Probe{
 								ProbeHandler: corev1.ProbeHandler{
 									HTTPGet: &corev1.HTTPGetAction{Port: intstr.FromInt(80)},