Add clear-firewall role to bandit playbook

This change adds the clear-firewall role to the osh-infra-bandit
playbook to resolve an issue with coredns not coming up when
this job is ran on an ubuntu focal node.

Change-Id: I189ceff30271f3a478aff697b84709b19d0b09fc

playbooks/osh-infra-bandit.yaml

@@ -2,6 +2,9 @@
 - hosts: all
   name: openstack-helm-infra-bandit
   tasks:
+    - name: Clear firewall
+      include_role:
+        name: clear-firewall
 
     - name: Install Required Packages and Setup Host
       shell: |