How do I to attach a managed disk to a VM Scale Set?

I’m creating a Virtual Machine Scale Set for our Azure DevOps buildagents and am looking into attaching a shared managed disk for our Docker images and package caches. I know this is possible in Azure as we’ve manually set it up before, but I can’t seem to figure out how to do it via Terraform.

It’s possible for individual Virtual Machines with azurerm_linux_virtual_machine and azurerm_virtual_machine_data_disk_attachment but there is no such option for azurerm_linux_virtual_machine_scale_set and the attachment can only reference a VM, not an entire scaleset.

Is it just not implemented in the current version or is there some other way I should go about it?