Add ovn-kubernetes version bump to CI Maintenance docs

[dfarrell07]

We should document the need to do bumps like submariner-io/submariner#2478 in these docs: https://submariner.io/development/building-testing/ci-maintenance/

We also want to build the ovn-k image and store it for reuse, vs building each time (different task). Once that's done, we may be able to automate both steps in the release process. For now, we can make an issue that blocks RC0 and points to the docs to remind us to check what needs to be updated.

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[github-actions]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further
activity occurs. Thank you for your contributions.

[dfarrell07]

There is still a reference in Shipyard that needs to be updated in https://github.com/submariner-io/shipyard/blob/devel/scripts/shared/lib/clusters_kind, in the prepare_ovn function.