Investigate Kubernetes 1.28 support

This issue is only about the investigation. We want to deliver the necessary work in the following three milestone.

Definition of done

As part of the investigation, open the necessary issues for the following steps if needed and refine them with the team:

• Add 1.28 to supported k3s versions in test-utils-k3s/k3s-gitlab-ci (used for CI test jobs). See example MR.
• Bump test-utils/k3s-gitlab-ci version in k8s-agent-qa.
• Bump the KUBECTL and test-utils/k3s-gitlab-ci k3s version in helm-install-image. See example MR and how to review.
• Bump the helm-install-image version in the cluster-applications. See example MR.
• Update auto-deploy-image.
  1. Bump k3s-gitlab-ci version in the test matrix. See example MR.
  2. Bump the HELM_INSTALL_IMAGE_VERSION in .gitlab-ci.yml to the helm-install-image version released in the above step. This is used in the Dockerfile.
  3. Bump the auto-deploy image in the GitLab - Auto Deploy template and test Auto Deploy
• Make sure that the applications versions in Cluster Management project template support Kubernetes 1.28.
  • Install all apps in a Kubernetes cluster with the version being tested, and possibly bump the app versions, or do a fix.

References

• https://kubernetes.io/blog/2023/08/15/kubernetes-v1-28-release/