fix(k8s): add warning

Author: bene2k1

pages/instances/how-to/migrate-volumes-snapshots-to-sbs.mdx

@@ -45,6 +45,10 @@ Alternatively, you can use the [snapshot export/import feature](/instances/api-c
 - A Scaleway account logged into the [console](https://console.scaleway.com)
 - An [Instance](/instances/how-to/create-an-instance/) using [Block Storage volumes](/block-storage/how-to/create-a-volume/)
 
+<Message type="important">
+  Volumes **created and managed though Kubernetes** do not fall within the scope of the migration described in this page. Find specific instructions for migrating Kubernetes volumes behind the Scaleway Block Storage API [in the managing storage for Kubernetes documentation](/kubernetes/api-cli/managing-storage/#upgrading-to-csi-version-03).
+</Message>
+
 <Message type="tip">
   - The easiest way to migrate your Block Storage volumes and snapshots is by using the [Scaleway Command Line Interface (CLI)](/scaleway-cli/quickstart/) tool.
   - If you encounter an error about quota limitations during the migration process, [contact our support team](https://console.scaleway.com/support/tickets/create) for assistance.