Remove olaf from documentation team

[github-actions[bot]]

🚀 Deployed on https://6648dce333bf64f72bc78326--nixos-homepage.netlify.app

[fricklerhandwerk]

@olaf many thanks for all your time, it was great working with you. Sad to see you go. You wrote the invaluable NixOS VM test tutorials, which were read by hundreds of people and highly appreciated.