replace k8s-ingress-image-push with SIG K8s Infra project and promote images to registry.k8s.io

[BenTheElder]

FYI @kubernetes/sig-k8s-infra-leads one more google.com project snuck through ... the naming suggests a sig-k8s-infra kubernetes.io project but it's not.

https://cs.k8s.io/?q=k8s-ingress-image-push&i=nope&literal=nope&files=&excludeFiles=&repos=

https://github.com/kubernetes/test-infra/blob/6e449eb66acd4f0073743de9a75183b07c19c7f0/config/jobs/image-pushing/k8s-staging-ingress-gce.yaml#L19

ingress-gce/cloudbuild.yaml

Line 12 in 674a2c2

- REGISTRY=gcr.io/k8s-ingress-image-push

Possibly belongs here:
https://github.com/kubernetes/k8s.io/blob/8ef52c0e65b67ce9091d9bac376ac45132d7ea9e/registry.k8s.io/images/k8s-staging-networking/images.yaml#L46

[aojea]

The work here is basically take the occurrences in https://cs.k8s.io/?q=k8s-ingress-image-push&i=nope&literal=nope&files=&excludeFiles=&repos=

and replace gcr.io/k8s-ingress-image-push by gcr.io/k8s-staging-networking

[BenTheElder]

I think you'll also want to then take the next image build, promote it to registry.k8s.io, (see the docs at https://registry.k8s.io) and update any user-facing references to use the registry.k8s.io image. #sig-k8s-infra in https://slack.k8s.io can help with this.

Staging registries are not supported for end-user consumption and have automatic 90 day TTL.

The previous google.com staging registry is also probably not desired for end-user hosting in case it becomes subject to security policies for example.