This patch does a rollback of Metallb after an outage of all
loadbalancer IPs in the cluster without any useful events or error logs.

This reverts commit 6c10ae98.

This patch removes the no longer needed encryption regex from the sops
configuration. This regex was introduced when using the values field to
set certain URLs in the oauth2-proxy config. Since this was replaced
with secret-based config overwrites as part of the helmrelease, the
regex can safely be dropped.

This patch introduces a new component that can be used to restrict all
ingress resources to a predefined set of whitelisted IP addresses. This
reduces the duplication in ingress objects for the same rule sets over
and over again.

This patch adjusts the component for oauth2-proxy to also include a
patching mechism for all kustomize-defined Ingress objects to be
restricted.

The first patch that "adds" `{}` to `/metadata/labels` would replace any
existing labels resulting in unexpected behaviour. Instead we rely on
the preexistence of the labels field in the namespace.