Update online-backup.adoc

Author: NataliaIvakina

modules/ROOT/pages/backup-restore/online-backup.adoc

@@ -233,8 +233,6 @@ It controls the timeout duration of the catchup protocol, which is the underlyin
 You can also tune up xref:configuration/configuration-settings.adoc#_checkpoint_settings[the Checkpoint settings] or check that your disks are performant enough to handle the load. 
 For more information, see xref:performance/disks-ram-and-other-tips.adoc#performance-checkpoint-iops-limit[Checkpoint IOPS limit].
 
-Periods of high traffic may also impact the duration of checkpointing -- and thus the success of a backup job.
-
 To read more about checkpointing, see xref:database-internals/checkpointing.adoc[Database internals -> Checkpointing and log pruning].