Add service account.

nix/kubernetes/keys/package/k8s-service-account/files/ca-config.json

@@ -0,0 +1,13 @@
+{
+  "signing": {
+    "default": {
+      "expiry": "8760h"
+    },
+    "profiles": {
+      "kubernetes": {
+        "usages": ["signing", "key encipherment", "server auth", "client auth"],
+        "expiry": "8760h"
+      }
+    }
+  }
+}

nix/kubernetes/keys/package/k8s-service-account/files/service-account-csr.json

@@ -0,0 +1,16 @@
+{
+  "CN": "service-accounts",
+  "key": {
+    "algo": "rsa",
+    "size": 2048
+  },
+  "names": [
+    {
+      "C": "US",
+      "L": "Portland",
+      "O": "Kubernetes",
+      "OU": "Kubernetes The Hard Way",
+      "ST": "Oregon"
+    }
+  ]
+}