K8S-4511: Update upgrade howto docs to include arbiter nodes in upgra…#60

TimLFletcher merged 1 commit intorelease/2.9couchbase/docs-operator:release/2.9from

K8S-4511-node-upgrade-order-arbitercouchbase/docs-operator:K8S-4511-node-upgrade-order-arbiterCopy head branch name to clipboard