Add ECK 2.14

[barkbay]

This adds the ECK 2.14 branch to the build list. ECK 2.14.0 is planned for release on Thu, Aug 08 2024. Please do not merge until the day before (Wed, Aug 07)

[github-actions[bot]]

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[barkbay]

INFO:build_docs:asciidoctor: WARNING: invalid reference: release-notes-2.14.0

Releases notes are coming in https://github.com/elastic/cloud-on-k8s/pull/7962