Skip test that is not relevant to Quantum

Quantum allows duplicate names for security groups,
thus this test must be skipped.

bug #1194468

(cherry picked from commit 30d6ae7a317a38a78c7db88e33834f5541175221)

Conflicts:
	tempest/tests/compute/security_groups/test_security_groups.py

Change-Id: Ic54e5b4b7f7d95a0a6db568fb9a66a566a101fc9