[openstack-helm] Nominate Doug Goldstein (cardoe) as a core reviewer

Hi team, I am writing to nominate Doug Goldstein (cardoe) as a member of the Openstack-helm core reviewers team. He's been actively contributing to the project during the last few release cycles and brought many valuable ideas (both technical and organizational). I also think it is important that our project has different companies represented in this important role. Please let me know what you think. -- Best regards, Kozhukalov Vladimir