OpenStack provides two ways for VMs to access metadata: metadata service and config drive.
By default, it uses the metadata service.
To use the config drive approach, you need to enable it when creating the Machine Deployment.
When creating a new User Cluster, you can enable this option in the Initial Node step.

You can also enable it for new Machine Deployments when creating them from the Add Machine Deployment dialog.

Admins can enforce the use of the config drive for all newly created Machine Deployments in a specific datacenter from the Admin Settings.
In the Admin Settings page, navigate to the Datacenters section.

Enable the Enable Config Drive option when adding or editing a datacenter for the OpenStack provider.

This will enforce the config drive for all newly created Machine Deployments in that datacenter.