Rename references to compute security groups client

The single network client is being split out into multiple
clients, one of which will be called SecurityGroupsClient. This patch
renames references to the compute security groups client
(security_groups_client changed to compute_security_groups_client)
to avoid confusion or conflicts with the new neutron security
groups client in code that will reference both the nova and
neutron security groups clients.

Partially implements blueprint consistent-service-method-names

Change-Id: Ic454de109e646b070d37f2976b723a6f1d184874
diff --git a/tempest/scenario/manager.py b/tempest/scenario/manager.py
index 24877f4..c304136 100644
--- a/tempest/scenario/manager.py
+++ b/tempest/scenario/manager.py
@@ -55,7 +55,8 @@
         cls.images_client = cls.manager.images_client
         cls.keypairs_client = cls.manager.keypairs_client
         # Nova security groups client
-        cls.security_groups_client = cls.manager.security_groups_client
+        cls.compute_security_groups_client = (
+            cls.manager.compute_security_groups_client)
         cls.security_group_rules_client = (
             cls.manager.security_group_rules_client)
         cls.servers_client = cls.manager.servers_client
@@ -286,7 +287,7 @@
         return volume
 
     def _create_loginable_secgroup_rule(self, secgroup_id=None):
-        _client = self.security_groups_client
+        _client = self.compute_security_groups_client
         _client_rules = self.security_group_rules_client
         if secgroup_id is None:
             sgs = _client.list_security_groups()['security_groups']
@@ -328,13 +329,14 @@
         # Create security group
         sg_name = data_utils.rand_name(self.__class__.__name__)
         sg_desc = sg_name + " description"
-        secgroup = self.security_groups_client.create_security_group(
+        secgroup = self.compute_security_groups_client.create_security_group(
             name=sg_name, description=sg_desc)['security_group']
         self.assertEqual(secgroup['name'], sg_name)
         self.assertEqual(secgroup['description'], sg_desc)
-        self.addCleanup(self.delete_wrapper,
-                        self.security_groups_client.delete_security_group,
-                        secgroup['id'])
+        self.addCleanup(
+            self.delete_wrapper,
+            self.compute_security_groups_client.delete_security_group,
+            secgroup['id'])
 
         # Add rules to the security group
         self._create_loginable_secgroup_rule(secgroup['id'])