Zero-downtime update doc: Ensure the deploy node is not in-use
To avoid downtime, we should make it explicit that the deploy node must not be in-use during upgrades: * [x] Geo HA and single-node update instructions => https://gitlab.com/gitlab-org/omnibus-gitlab/-/merge_requests/3902 * [ ] Non-Geo HA update instructions * [ ] Single-node update instructions (temporarily add a separate deploy node?)
issue