Add OS type variable to each vmpooler target

[gavindidrichsen]

Prior to this change, it was impossible to visually inspect the bolt inventory and know what OS each VM was. Now there's a new vars.type added to each target that clearly marks this. For example:

---
targets:
- name: evil-management
  uri: evil-management.delivery.puppetlabs.net
  vars:
    type: win-2022-x86_64
groups:
- name: windows
  config:
    transport: winrm
    winrm:
      user: Administrator
      password:
        _plugin: env_var
        var: VMPOOLER_WINDOWS_PASSWORD
      ssl: false
  facts:
    role: windows
  targets:
  - evil-management
- name: linux
  config:
    transport: ssh
    ssh:
      native-ssh: true
      load-config: true
      login-shell: bash
      tty: false
      host-key-check: false
      run-as: root
      user: root
  facts:
    role: linux
  targets: []