[Stateless SG] Add test to check creation of the stateless SG

This patch adds test which creates stateless SG, checks if
it is stateful and if corresponding ACLs in OVN have correct
action, which is "allow-stateless".

Depends-On: https://review.opendev.org/c/x/devstack-plugin-tobiko/+/872732

Change-Id: I6d49f1be6fba92862d75c124d4e42bf43946225b

tobiko/tests/scenario/neutron/test_security_groups.py

@@ -184,3 +184,35 @@ class StatelessSecurityGroupTest(BaseSecurityGroupTest):
         )
         self._check_sg_rule_in_ovn_nb_db(new_rule['id'],
                                          neutron.STATEFUL_OVN_ACTION)
+
+    def test_create_stateless_security_group(self):
+        """Test that stateless security group can be created.
+
+        This test checks if creation of the stateless SG is working fine
+        and if OVN's ACLs corresponding to the SG's rules have correct
+        action which is "allow-stateless".
+
+        Steps:
+        1. Create stateless security group,
+        2. Check if ACLs corresponding to the rules from that SG have
+           "action-stateless" action,
+        3. Add new SG rule in the SG,
+        4. Check action of the ACL corresponding to the newly created SG rule.
+        """
+        sg = neutron.create_security_group(
+            name="test_stateless_SG",
+            stateful=False
+        )
+        self.assertFalse(sg['stateful'])
+        self._check_sg_rules_in_ovn_nb_db(sg, neutron.STATELESS_OVN_ACTION)
+        new_rule = neutron.create_security_group_rule(
+            sg['id'],
+            port_range_min=1111,
+            port_range_max=1111,
+            ethertype="IPv4",
+            protocol="tcp",
+            description="test_new_security_group_is_statefull_SG rule",
+            direction="ingress"
+        )
+        self._check_sg_rule_in_ovn_nb_db(new_rule['id'],
+                                         neutron.STATELESS_OVN_ACTION)