[Cherry-pick][5.x] Clarify not running in single to cluster migration (#2426) (#2428)

# Backport

This will backport the following commits from `dev` to `5.x`:
- [Clarify not running in single to cluster migration
(#2426)](#2426)

<!--- Backport version: 9.5.1 -->

### Questions ?
Please refer to the [Backport tool
documentation](https://github.com/sorenlouv/backport)

Co-authored-by: sumyiren <[email protected]>

Author: github-actions[bot]

modules/ROOT/pages/clustering/setup/single-to-cluster.adoc

@@ -22,7 +22,8 @@ See xref:clustering/setup/analytics-cluster.adoc[] for more information on analy
 ======
 
 In this example, a standalone server named `server01` is running and two additional servers, `server02` and `server03`, are to be added to form a cluster.
-The two additional servers are configured according to xref:clustering/setup/deploy.adoc#cluster-example-configure-a-three-primary-cluster[Configure a cluster with three servers] and are _not_ running.
+The two additional servers are configured according to xref:clustering/setup/deploy.adoc#cluster-example-configure-a-three-primary-cluster[Configure a cluster with three servers].
+These two new servers should _not_ be started up yet.
 Neo4j Enterprise Edition is installed on all three servers.
 
 Start by stopping the standalone server.