cluster: bump rook to 1.0.6

In preparation for updating to 1.1.0, which will be much more involved.

Also fix a typo in registry.libsonnet, whoops.

Change-Id: I7668bf53c7580f99fdf56fe6227f04a468f8de50
diff --git a/cluster/kube/lib/registry.libsonnet b/cluster/kube/lib/registry.libsonnet
index e65f569..2df6da6 100644
--- a/cluster/kube/lib/registry.libsonnet
+++ b/cluster/kube/lib/registry.libsonnet
@@ -312,7 +312,7 @@
             },
         },
 
-        registryStorageUser: kue.CephObjectStoreUser("registry") {
+        registryStorageUser: kube.CephObjectStoreUser("registry") {
             metadata+: {
                 namespace: "ceph-waw2",
             },