Remove setup_credentials from orchestration tests

We don't need to override setup_credentials class method for
orchestration api tests.

Change-Id: I36f23e655b80da8b129d2a78e76824e5b363b4c8
Partial-Bug: #1539692
diff --git a/tempest/api/orchestration/base.py b/tempest/api/orchestration/base.py
index c93b5ed..f833bf3 100644
--- a/tempest/api/orchestration/base.py
+++ b/tempest/api/orchestration/base.py
@@ -34,12 +34,6 @@
             raise cls.skipException("Heat support is required")
 
     @classmethod
-    def setup_credentials(cls):
-        super(BaseOrchestrationTest, cls).setup_credentials()
-        stack_owner_role = CONF.orchestration.stack_owner_role
-        cls.os = cls.get_client_manager(roles=[stack_owner_role])
-
-    @classmethod
     def setup_clients(cls):
         super(BaseOrchestrationTest, cls).setup_clients()
         cls.orchestration_client = cls.os.orchestration_client
diff --git a/tempest/api/orchestration/stacks/test_neutron_resources.py b/tempest/api/orchestration/stacks/test_neutron_resources.py
index 09e863e..3c9dcb1 100644
--- a/tempest/api/orchestration/stacks/test_neutron_resources.py
+++ b/tempest/api/orchestration/stacks/test_neutron_resources.py
@@ -35,11 +35,6 @@
             raise cls.skipException("Neutron support is required")
 
     @classmethod
-    def setup_credentials(cls):
-        cls.set_network_resources()
-        super(NeutronResourcesTestJSON, cls).setup_credentials()
-
-    @classmethod
     def setup_clients(cls):
         super(NeutronResourcesTestJSON, cls).setup_clients()
         cls.network_client = cls.os.network_client
diff --git a/tempest/api/orchestration/stacks/test_swift_resources.py b/tempest/api/orchestration/stacks/test_swift_resources.py
index c0f1c4b..fea5e37 100644
--- a/tempest/api/orchestration/stacks/test_swift_resources.py
+++ b/tempest/api/orchestration/stacks/test_swift_resources.py
@@ -30,14 +30,6 @@
             raise cls.skipException("Swift support is required")
 
     @classmethod
-    def setup_credentials(cls):
-        super(SwiftResourcesTestJSON, cls).setup_credentials()
-        stack_owner_role = CONF.orchestration.stack_owner_role
-        operator_role = CONF.object_storage.operator_role
-        cls.os = cls.get_client_manager(
-            roles=[stack_owner_role, operator_role])
-
-    @classmethod
     def setup_clients(cls):
         super(SwiftResourcesTestJSON, cls).setup_clients()
         cls.account_client = cls.os.account_client