Drop support for EOLed Kubernetes versions

[michi-covalent]

Remove EOLed Kubernetes versions from Ginkgo PR and scheduled runs, and update the docs accordingly.

Ref: https://kubernetes.io/releases/patch-releases/

[sayboras]

LGTM ✅

[michi-covalent]

/test

[michi-covalent]

i'll bring this up in the community meeting today

[aanm]

To accept the PR we should do a couple more things:

• Document our testing criteria in the documentation, under Documentation/network/kubernetes/compatibility.rst and Documentation/network/kubernetes/requirements.rst should be fine
• Keep the list of cloud provider k8s versions that we test in the list on those files.
• Making sure that by removing the k8s versions that we aren't dropping testing on specific kernel versions. For example, kernel 4.19 is only tested with k8s 1.19 so if we are dropping it then we need to change the test of 4.19 to be 1.26. That's defined in .github/actions/ginkgo/main-k8s-versions.yaml.

[michi-covalent]

thanks for the feedback andre, i'll update the docs.

regarding the kernel version, don't we also test 4.19 with k8s 1.27? https://github.com/cilium/cilium/blob/main/.github/actions/ginkgo/main-k8s-versions.yaml#L11-L16

[michi-covalent]

back to draft to address feedback

[michi-covalent]

/test

[aanm]

LGTM but there's one bullet point missing:

Making sure that by removing the k8s versions that we aren't dropping testing on specific kernel versions. For example, kernel 4.19 is only tested with k8s 1.19 so if we are dropping it then we need to change the test of 4.19 to be 1.26. That's defined in .github/actions/ginkgo/main-k8s-versions.yaml.

[michi-covalent]

Making sure that by removing the k8s versions that we aren't dropping testing on specific kernel versions. For example, kernel 4.19 is only tested with k8s 1.19 so if we are dropping it then we need to change the test of 4.19 to be 1.26. That's defined in .github/actions/ginkgo/main-k8s-versions.yaml.

thanks @aanm, yeah this is the part i wasn't sure about. don't we already test 4.19 with 1.27, or am i reading this wrong? 💭 https://github.com/cilium/cilium/blob/main/.github/actions/ginkgo/main-k8s-versions.yaml#L11-L16

[michi-covalent]

requesting additional review from @joestringer 🚀 🙏

[michi-covalent]

/test

[aanm]

Making sure that by removing the k8s versions that we aren't dropping testing on specific kernel versions. For example, kernel 4.19 is only tested with k8s 1.19 so if we are dropping it then we need to change the test of 4.19 to be 1.26. That's defined in .github/actions/ginkgo/main-k8s-versions.yaml.

thanks @aanm, yeah this is the part i wasn't sure about. don't we already test 4.19 with 1.27, or am i reading this wrong? 💭 https://github.com/cilium/cilium/blob/main/.github/actions/ginkgo/main-k8s-versions.yaml#L11-L16

@michi-covalent this file is also relevant https://github.com/cilium/cilium/blob/main/.github/actions/ginkgo/main-focus.yaml. We need to make sure we are removing the sections that are excluded as well as readjust it if necessary.

[michi-covalent]

/test