CSI implement topologies support

[tgross]

The MVP for CSI in the 0.11.0 release of Nomad did not include support for topologies. This issue is both for getting the configuration plumbed through and adding the required bits to the scheduler.

[tgross]

A note for myself from some research: the only commonly-used plugin I've been able to find that implements topology is Ceph. MooseFS has a "topology" flag for its parameters but confusingly, this doesn't look like it's the same as the CSI spec topology.

[tgross]

Follow-up on plugins: I discovered today that the gcp-compute-persistent-disk-csi-driver driver expects topologies to be supported for the CreateVolume RPC. So you can register a GCP volume but not create one, as you'll get an error like the following:

$ nomad volume create ./volume.hcl
Error creating volume: Unexpected response code: 500 (1 error occurred:
        * controller create volume: rpc error: controller create volume: CSI.ControllerCreateVolume: volume "searchzk" snapshot source &{"" ""} is not compatible with these parameters: rpc error: code = InvalidArgument desc = CreateVolume failed to pick zones for disk: failed to pick zones from topology: need 1 zones from topology, only got 0 unique zones

[tgross]

Noting that this blocks resolving #11778 and #10891. We intend to ship this before CSI is marked GA.

[github-actions]

I'm going to lock this issue because it has been closed for 120 days ⏳. This helps our maintainers find and focus on the active issues.
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