Move warn clause as a shell task option.

The warn clause should be included inside an args
subsection, otherwise the task will fail syntactically
with 'warn' is not a valid attribute for a Task.

Closes-Bug: #1824496
Change-Id: I217437c4d104475c8ea415dd178940c40264e0b0

deployment/tripleo-packages/tripleo-packages-baremetal-puppet.yaml

@@ -176,7 +176,8 @@ outputs:
             - name: remove old OpenvSwitch package(s) if version doesn't match
               shell: |
                 rpm -e --noscripts --nopreun --nopostun --notriggers --nodeps $(rpm -qa 'openvswitch{{ package_suffix|default('') }}*' | grep -v 'selinux')
-              warn: false
+              args:
+                warn: false
               when: new_ovs_version != current_ovs_version
             - name: install/upgrade OpenvSwitch LP package
               package: