Fix permission issue when removing octavia temp dirs

Temporary directories were created with 'become: true' parameter,
removing them without the same parameter might lead to permission denied
error.

Closes-Bug: #1863599
Change-Id: I61db5d3b2ada590f8cbc0e93889872e1746b621c

deployment/octavia/octavia-deployment-config.j2.yaml

@@ -347,6 +347,7 @@ outputs:
                 ANSIBLE_LOG_PATH:  "{{ octavia_log_dir }}/octavia-ansible.log"
               shell:  "{{ config_octavia_cmd }}"
             - name: Purge temp dirs
+              become: true
               file:
                 state: absent
                 path: "{{ item }}"