Enable aggregator routing on kind clusters

This should make it easier for us to to notice if something is wrong
with our service (especially in any future kubectl tests we add).

Signed-off-by: Monis Khan <mok@vmware.com>

hack/lib/kind-config/single-node.yaml

@@ -24,3 +24,18 @@ nodes:
       containerPort: 31235
       hostPort: 12346
       listenAddress: 127.0.0.1
+kubeadmConfigPatches:
+- |
+  apiVersion: kubeadm.k8s.io/v1beta2
+  kind: ClusterConfiguration
+  apiServer:
+    extraArgs:
+      # To make sure the endpoints on our service are correct (this mostly matters for kubectl based
+      # installs where kapp is not doing magic changes to the deployment and service selectors).
+      # Setting this field to true makes it so that the API service will do the service cluster IP
+      # to endpoint IP translations internally instead of relying on the network stack (i.e. kube-proxy).
+      # The logic inside the API server is very straightforward - randomly pick an IP from the list
+      # of available endpoints.  This means that over time, all endpoints associated with the service
+      # are exercised.  For whatever reason, leaving this as false (i.e. use kube-proxy) appears to
+      # hide some network misconfigurations when used internally by the API server aggregation layer.
+      enable-aggregator-routing: "true"