OSDOCS#12867: Noting that SNO can't have workloads running to shut down

Author: bergerhoffer

modules/graceful-shutdown.adoc

@@ -17,6 +17,7 @@ You can shut down a cluster until a year from the installation date and expect i
 
 * You have access to the cluster as a user with the `cluster-admin` role.
 * You have taken an etcd backup.
+* If you are running a {sno} cluster, you must evacuate all workload pods off of the cluster before you shut it down.
 
 .Procedure
 
@@ -77,7 +78,7 @@ Ensure that the control plane node with the API VIP assigned is the last node pr
 $ for node in $(oc get nodes -o jsonpath='{.items[*].metadata.name}'); do oc debug node/${node} -- chroot /host shutdown -h 1; done <1>
 ----
 +
-<1> `-h 1` indicates how long, in minutes, this process lasts before the control plane nodes are shut down. For large-scale clusters with 10 nodes or more, set to `-h 10` or longer to make sure all the compute nodes have time to shut down first. 
+<1> `-h 1` indicates how long, in minutes, this process lasts before the control plane nodes are shut down. For large-scale clusters with 10 nodes or more, set to `-h 10` or longer to make sure all the compute nodes have time to shut down first.
 +
 .Example output
 [source,terminal]