docs: Add release notes for kubespray v2.26.0-ck8s2

[Ajarmar]

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[Ajarmar]

The apps documentation auto-generation is failing in the "pre-commit" workflow: https://github.com/elastisys/welkin/actions/runs/12786259591/job/35642973802?pr=1023

Is it fine to merge the PR despite this? @elastisys/goto-public-docs @elastisys/qa

[aarnq]

The apps documentation auto-generation is failing in the "pre-commit" workflow: https://github.com/elastisys/welkin/actions/runs/12786259591/job/35642973802?pr=1023

Is it fine to merge the PR despite this? @elastisys/goto-public-docs @elastisys/qa

I suggest waiting on elastisys/compliantkubernetes-apps#2393, it should fix the issue.