Restart dnsmasq after clearing iptables

During a test run, iptables is cleared and NATs are implemented by dnsmasq.
On subsequent runs, the clearing of iptables blows out the NATs and the
dnsmasq restart handler is not properly triggered. This patch shifts the task
to where the handler can be properly notified.

Change-Id: I4a274e0bfc6b099dc465ee11087977836b66f249

test-prepare-host.yml

@@ -99,6 +99,15 @@
   roles:
     - role: "lxc_hosts"
 
+  post_tasks:
+    - name: Trigger dnsmasq restart
+      command: /bin/true
+      changed_when:
+        - (lxc_net_manage_iptables is defined) and (lxc_net_manage_iptables | bool)
+        - (iptables_clear is defined) and (iptables_clear is changed)
+      notify:
+      - Restart dnsmasq
+
 - name: Playbook for configuring test host networking
   hosts: localhost
   # This set of tasks runs against localhost
@@ -206,14 +215,6 @@
       setup:
         gather_subset: "all"
 
-    - name: Trigger dnsmasq restart
-      command: /bin/true
-      changed_when:
-        - (lxc_net_manage_iptables is defined) and (lxc_net_manage_iptables | bool)
-        - (iptables_clear is defined) and (iptables_clear is changed)
-      notify:
-        - Restart dnsmasq
-
     - name: Set interfaces fact
       set_fact:
         active_interfaces: |-