Tests: Remove SG's specific flows tests
Tests: Remove SG's specific flows tests

These tests are very specific and hard to maintain.
Since this is already being tested in the full Security Group App test,
it doesn't add an actual value for DragonFlow.

Change-Id: I9e4aad32edbd6abb5695ec8ae0b01be58eba202a

openstack/dragonflow,openstack/dragonflow,openstack/dragonflow