create_server method full removal

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

There is no need to have create_server definition in ironic scenario manager

Replaced methods:
	* create_server

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: I781cbf90e283bd8a3be4ad3e6aa7c13f280444e0
diff --git a/ironic_tempest_plugin/manager.py b/ironic_tempest_plugin/manager.py
index 2dcf18a..9f992be 100644
--- a/ironic_tempest_plugin/manager.py
+++ b/ironic_tempest_plugin/manager.py
@@ -84,17 +84,6 @@
     # The create_[resource] functions only return body and discard the
     # resp part which is not used in scenario tests
 
-    def create_server(self, name=None, image_id=None, flavor=None,
-                      validatable=False, wait_until='ACTIVE',
-                      clients=None, **kwargs):
-        return super().create_server(name=name,
-                                     image_id=image_id,
-                                     flavor=flavor,
-                                     validatable=validatable,
-                                     wait_until=wait_until,
-                                     clients=clients,
-                                     **kwargs)
-
     def get_remote_client(self, ip_address, username=None, private_key=None):
         """Get a SSH client to a remote server