not compatible with Facter 4

[vchepkov]

Affected Puppet, Ruby, OS and module versions/distributions

• Puppet: 6.21.1
• Ruby: 2.5.8p224
• Distribution: RHEL8
• Module version: 4.0.0

How to reproduce (e.g Puppet code you use)

either enable facterng or run puppet facts diff

What are you seeing

  "rhsm_repos.0": {
    "new_value": null,
    "old_value": "codeready-builder-for-rhel-8-x86_64-rpms"
  },
  "rhsm_repos.1": {
    "new_value": null,
    "old_value": "rhel-8-for-x86_64-baseos-rpms"
  },
  "rhsm_repos.2": {
    "new_value": null,
    "old_value": "rhel-8-for-x86_64-appstream-rpms"
  },
  "rhsm_subscription_type": {
    "new_value": null,
    "old_value": "rhsm"
  }