Add support for EL8

[treydock]

Pull Request Checklist

Description

Add support for EL8 by installing EL7 packages.

[ghoneycutt]

why dig? why not just address the facts by name?

[treydock]

Because it would require more complete unit tests because if you do $facts['os']['family'] and $facts['os'] is not defined, you get errors. Dig is much safer when traversing deep hash in case facts are missing.

[treydock]

Also ever since Puppet 5 dig is the better way to walk a hash, just safer and less verbose than checking each intermediate key exists. Might have been around since Puppet 4, but I know it's built-in to Puppet 5.

[ghoneycutt]

These facts always exist and if they didn't something would be terribly wrong. This makes sense to me if we are digging into data structures that are more dynamic. Please just access the facts as that makes it easier to read.

[treydock]

I tried using without dig and that results is a majority of the unit tests failing because the unit tests do not use rspec-puppet-facts and instead rely on specifying facts manually and many of the facts we need in this change are not defined. So using dig is a sort of soft fail approach vs a hard fail and right now the unit tests are getting a hard fail even though in the real world the change would not cause failures. Do we want to go through the effort of updating the numerous unit tests or just stick with the "soft fail" approach of using dig that does not require lots of unit test updates?

Looks like to remove the use of dig would require updating nearly every single unit test which is a big change:

Finished in 1 minute 8.15 seconds (files took 2.11 seconds to load)
963 examples, 606 failures

[ghoneycutt]

Released in v3.7.0