FWaaS L3 Driver API [1] has been updated in Rocky by adding
notification callback events without Unit Test.
It might raise some unexpected regression in further.
This patch intends to add UTs for Driver API Neutron-FWaaS.
[1] https://review.openstack.org/#/c/578718/
Co-Authored-By: Kim Bao Long <longkb@vn.fujitsu.com>
Change-Id: I7a1ffa1ad6ba370e63a7b87f697ac9f3e9d9b57a