Ensure there is no confusion about the scope of rancher-backup

[philippebi]

Add a note to the documentation to ensure there is no confusion about the scope of the rancher-backup application.

[LucasSaintarbor]

@philippebi Made a small suggestion. May you add this note to versioned_docs/version-2.11/how-to-guides/new-user-guides/backup-restore-and-disaster-recovery/backup-restore-and-disaster-recovery.md and any other versions prior to v2.11 if needed?

[LucasSaintarbor]

Suggested change

	`rancher-backup` handles the backup and restore of Rancher's core components only. It does not include applications deployed from the local cluster repositories, such as `rancher-monitoring` or `rancher-logging`, in the backup process. To back up these applications, consider using third-party tools or manually exporting and redeploying Helm charts and custom resources.
	`rancher-backup` only handles backing up and restoring Rancher's core components. It does not back up applications deployed from the local cluster repositories, such as `rancher-monitoring` or `rancher-logging`. To back up these applications, consider using third-party tools or manually exporting and redeploying Helm charts and custom resources.

[philippebi]

I recently discovered that the situation is a bit more complex than I initially thought, and my previous examples may not have been the best, as some components of rancher-monitoring and rancher-logging, such as secrets, namespaces, service accounts, roles, and role bindings, are indeed backed up. However, these two applications are not fully restored automatically, and their Helm charts need to be manually reinstalled after the restore process.

I would add this line to clarify this:

rancher-backup only handles backing up and restoring Rancher's core components. It does not back up applications deployed from the local cluster repositories. To back up these applications, consider using third-party tools or manually exporting and redeploying Helm charts and custom resources.

In the case of rancher-monitoring and rancher-logging, although their Helm charts must be manually reinstalled, their Kubernetes resources (e.g., namespaces, secrets, service accounts, roles, and role bindings) are part of the Rancher backup. It is necessary to ensure that both charts are working exactly as they did prior to the backup once reinstalled.

What do you think about it ?