nit: details CSI migration (#4693)

* details CSI migration

* Apply suggestions from code review

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

Author: louisportay

pages/kubernetes/api-cli/managing-storage.mdx

@@ -45,6 +45,8 @@ To identify your current CSI release version, navigate to the [Cockpit interface
   The Scaleway Block Volume Container Storage Interface (CSI) driver **v0.2** will reach its end of support on **February 28, 2025**.
 </Message>
 
+The migration moves volumes from the [Instances API](https://www.scaleway.com/en/developers/api/instance/) to the [Scaleway Block Storage API](https://www.scaleway.com/en/developers/api/block/). No volume detachment is expected, only a control plane restart.
+
 ### Using the API with curl
 
 You can trigger the migration to SBS-CSI using the following `curl` command: