ClearLinux: remove special casing

- put package install in system_packages
- docker should be handled by the approriate roles if used as container
  engine

roles/bootstrap_os/tasks/clear-linux-os.yml

@@ -1,16 +0,0 @@
----
-# ClearLinux ships with Python installed
-
-- name: Install basic package to run containers
-  package:
-    name: containers-basic
-    state: present
-
-- name: Make sure docker service is enabled
-  systemd_service:
-    name: docker
-    masked: false
-    enabled: true
-    daemon_reload: true
-    state: started
-  become: true