Kuryr-Kubernetes relies on watching resources in K8s API using an HTTP
stream served by kube-apiserver. In such a distributed system this is
sometimes unstable and e.g. etcd issues can cause some events to be
omitted. To prevent controller from such situations this patch makes
sure that periodically a full list of resources is fetched and injected
as events into the handlers.
We should probably do the same for kuryr-daemon watcher, but that case
is less problematic as it'll be restarted in event of ADD requests