[sfc] Remove _create_port & create_keypair

As tempest.scenario.manager was announced stable interface in Tempest
27.0.0[1] it can be now reused in plugins.

Removed methods:
   * _create_port
   * create_keypair

Etherpad concerning this effort:
https://etherpad.opendev.org/p/tempest-scenario-manager-cleanup

[1] https://docs.openstack.org/releasenotes/tempest/v27.0.0.html#release-notes-27-0-0

Change-Id: I44d2ebf2bd74e42474774c4ff72e3a3021a82983
diff --git a/neutron_tempest_plugin/sfc/tests/scenario/manager.py b/neutron_tempest_plugin/sfc/tests/scenario/manager.py
index 04962e4..8fe3b3e 100644
--- a/neutron_tempest_plugin/sfc/tests/scenario/manager.py
+++ b/neutron_tempest_plugin/sfc/tests/scenario/manager.py
@@ -61,30 +61,6 @@
     # The create_[resource] functions only return body and discard the
     # resp part which is not used in scenario tests
 
-    def _create_port(self, network_id, client=None, namestart='port-quotatest',
-                     **kwargs):
-        if not client:
-            client = self.ports_client
-        name = data_utils.rand_name(namestart)
-        result = client.create_port(
-            name=name,
-            network_id=network_id,
-            **kwargs)
-        self.assertIsNotNone(result, 'Unable to allocate port')
-        port = result['port']
-        self.addCleanup(test_utils.call_and_ignore_notfound_exc,
-                        client.delete_port, port['id'])
-        return port
-
-    def create_keypair(self, client=None):
-        if not client:
-            client = self.keypairs_client
-        name = data_utils.rand_name(self.__class__.__name__)
-        # We don't need to create a keypair by pubkey in scenario
-        body = client.create_keypair(name=name)
-        self.addCleanup(client.delete_keypair, name)
-        return body['keypair']
-
     def create_server(self, name=None, image_id=None, flavor=None,
                       validatable=False, wait_until='ACTIVE',
                       clients=None, **kwargs):
@@ -157,9 +133,9 @@
             for net in networks:
                 net_id = net.get('uuid', net.get('id'))
                 if 'port' not in net:
-                    port = self._create_port(network_id=net_id,
-                                             client=clients.ports_client,
-                                             **create_port_body)
+                    port = self.create_port(network_id=net_id,
+                                            client=clients.ports_client,
+                                            **create_port_body)
                     ports.append({'port': port['id']})
                 else:
                     ports.append({'port': net['port']})
diff --git a/neutron_tempest_plugin/sfc/tests/scenario/test_sfc.py b/neutron_tempest_plugin/sfc/tests/scenario/test_sfc.py
index 2f091e0..a009c54 100644
--- a/neutron_tempest_plugin/sfc/tests/scenario/test_sfc.py
+++ b/neutron_tempest_plugin/sfc/tests/scenario/test_sfc.py
@@ -65,10 +65,10 @@
             port_security_enabled=False)
         self.router2 = self._create_router()
         self.router3 = self._create_router()
-        self.router2_net1 = self._create_port(self.net1['id'])
+        self.router2_net1 = self.create_port(self.net1['id'])
         self._add_router_interface(
             self.router2['id'], self.router2_net1['id'])
-        self.router3_net1 = self._create_port(self.net1['id'])
+        self.router3_net1 = self.create_port(self.net1['id'])
         self._add_router_interface(
             self.router3['id'], self.router3_net1['id'])
         self.router2_net1_fixed_ip = self.router2_net1[
@@ -1063,13 +1063,13 @@
         self
     ):
         self.router4 = self._create_router()
-        self.router4_net1 = self._create_port(self.net1['id'])
+        self.router4_net1 = self.create_port(self.net1['id'])
         self._add_router_interface(
             self.router4['id'], self.router4_net1['id'])
         self.router4_net1_fixed_ip = self.router4_net1[
             'fixed_ips'][0]['ip_address']
         self.router5 = self._create_router()
-        self.router5_net1 = self._create_port(self.net1['id'])
+        self.router5_net1 = self.create_port(self.net1['id'])
         self._add_router_interface(
             self.router5['id'], self.router5_net1['id'])
         self.router5_net1_fixed_ip = self.router5_net1[