Refactor roles to support new variable schema

Add common-env and docker roles

roles/packages/tasks/repos.yml

@@ -8,6 +8,14 @@
         state: latest
         name: https://dl.fedoraproject.org/pub/epel/epel-release-latest-8.noarch.rpm
 
+    - name: Enable EPEL-Testing repository on CentOS 8s
+      lineinfile:
+        path: /etc/yum.repos.d/epel-testing.repo
+        regexp: "enabled=(0|1)"
+        line: "enabled=1"
+        insertbefore: "^$"
+        firstmatch: true
+
     - name: Enable the power tools repository on CentOS 8
       lineinfile:
         path: /etc/yum.repos.d/CentOS-PowerTools.repo