Fix OpenstackManager::install
diff --git a/tcp_tests/managers/openstack_manager.py b/tcp_tests/managers/openstack_manager.py
index b3b7a7e..4b554a9 100644
--- a/tcp_tests/managers/openstack_manager.py
+++ b/tcp_tests/managers/openstack_manager.py
@@ -31,4 +31,4 @@
     def install(self, commands):
         self.execute_commands(commands,
                               label='Install OpenStack services')
-        self._config.common_services.common_services_installed = True
+        self.__config.common_services.common_services_installed = True