Gather facts for host healthcheck

If the facts for the hosts are stale, or not present,
the playbook fails unless facts are gathered from the
container hosts. They are required because the "Ensuring
containers creation, connection and good behavior" play
uses host vars from the hosts.

Change-Id: Id4daf24f10e61a1800d73093c2aa5b9724a1c615

playbooks/healthcheck-hosts.yml

@@ -26,7 +26,7 @@
 # Ensure the lxc containers are properly setup
 - name: Ensuring hosts good behavior
   hosts: lxc_hosts
-  gather_facts: no
+  gather_facts: yes
   tasks:
     - name: Looking for dnsmasq process
       command: pgrep dnsmasq
@@ -34,7 +34,7 @@
 
 - name: Ensuring hosts good behavior
   hosts: nspawn_hosts
-  gather_facts: no
+  gather_facts: yes
   tasks:
     - debug:
         msg: "To be implemented. Please help."