Add schedmd-slurm-gcp-v6-nodeset-dynamic module

[mr0re1]

Motivation:

To simplify usage of "dynamic" instances

Usage:

  - id: dynamic_ns
    source: community/modules/compute/schedmd-slurm-gcp-v6-nodeset-dynamic
    use: [network, controller]
    settings:
      machine_type: n2-standard-2

  - id: dynamic_partition
    source: community/modules/compute/schedmd-slurm-gcp-v6-partition
    use: [dynamic_ns]
    settings:
      partition_name: mp
      is_default: true

  - id: controller
    source: community/modules/scheduler/schedmd-slurm-gcp-v6-controller
    use: [network, dynamic_partition]  

  - id: mig
    source: community/modules/compute/mig
    settings:
      versions:
      - name: highlander # there can be only one
        instance_template: $(dynamic_ns.instance_template_self_link)
      base_instance_name: $(dynamic_ns.node_name_prefix)```

[nick-stroud]

I am approving as I do not want to hold this up while I am out. If you strongly disagree with comments and want to move forward please get second opinion as tiebreaker.