Merge pull request #1118 from david22swan/CONT-779/puppet_8_clean

(Cont 779) Add Support for Puppet 8 / Drop Support for Puppet 6

Author: GSPatton

.fixtures.yml

@@ -2,9 +2,7 @@ fixtures:
   repositories:
     "stdlib": "https://github.com/puppetlabs/puppetlabs-stdlib.git"
     facts: 'https://github.com/puppetlabs/puppetlabs-facts.git'
-    puppet_agent: 
-      repo: 'https://github.com/puppetlabs/puppetlabs-puppet_agent.git'
-      ref: v4.12.1
+    puppet_agent: 'https://github.com/puppetlabs/puppetlabs-puppet_agent.git'
     provision: 'https://github.com/puppetlabs/provision.git'
   symlinks:
     "firewall": "#{source_dir}"