Replace outdated bitnami image builds in ci-images

Overview

Bitnami have announced that their large repository of open source charts/docker images are now being put behind a paywall effective August 28th.

The current Debian-based images will be moved from the current public catalog docker.io/bitnami to a legacy catalog docker.io/bitnamilegacy, and will no longer receive any updates.

A limited number of new hardened images are available under a new catalog docker.io/bitnamisecure.

Risks

Without any action from our part, from August 28th:

• Image builds pulling images from docker.io/bitnami will fail, breaking CI pipelines in multiple projects and affecting our ability to keep our tools and workloads up-to-date

Actions needed

Once we have an inventory of all bitnami images used (see #27169 (closed)), we will need to replace docker.io/bitnami with docker.io/bitnamilegacy everywhere present

Exit criteria

• We don't have any Docker image pulling from docker.io/bitnami
  • bitnami/kubectl is replaced
  • bitnami/fluentd is replaced