Fix broken test build for rolling deployments; ensure Ping is installed.

Author: geerlingguy

tests/deployments-rolling.yml

@@ -7,5 +7,11 @@
         groups: nodejs-api
       changed_when: false
 
+    - name: Update the apt cache.
+      apt: update_cache=yes cache_valid_time=600
+
+    - name: Ensure ping is present.
+      apt: name=iputils-ping state=present
+
 - import_playbook: ../deployments-rolling/playbooks/provision.yml
 - import_playbook: ../deployments-rolling/playbooks/deploy.yml