Release tooling snapshot, Sep 2021

Merge pull request kubernetes#1981 from saschagrunert/stage-ci

Remove `stage-ci` Makefile target

Release v0.7.0

Merge pull request kubernetes#1793 from justaugustus/backoff

pkg/cip: Use cenkalti/backoff/v4 to remove dep on k8s.io/apimachinery

Merge pull request kubernetes#1597 from saschagrunert/krel-anago-push

Add and integrate `krel anago push`