implemented as a separate command (kolla-ansible octavia-certificates)

Implements: blueprint implement-automatic-deploy-of-octavia

Co-Authored-By: wu.chunyang <wuchunyang@yovole.com>
Co-Authored-By: Radosław Piliszek <radoslaw.piliszek@gmail.com>

Change-Id: I2c5b26ce9e363f35c523865904a582f7960aa682