Replace deprecated tenant_id property

The tenant_id property of RestClient in tempest was deprecated in
25.0.0. This replaces the deprecated property by the new project_id
property to avoid the following warning.

WARNING tempest.lib.common.rest_client [-] Deprecated: "tenant_id"
property is deprecated for removal, use "project_id" instead

Depends-on: https://review.opendev.org/c/openstack/tempest/+/707938
Change-Id: Ie3c32f9f2278b78603a4214c5717df8691ba490a
diff --git a/neutron_tempest_plugin/api/base.py b/neutron_tempest_plugin/api/base.py
index 10821c1..b66fe0d 100644
--- a/neutron_tempest_plugin/api/base.py
+++ b/neutron_tempest_plugin/api/base.py
@@ -386,7 +386,7 @@
                     # Keep this network visible from current project
                     project_id = (kwargs.get('project_id') or
                                   kwargs.get('tenant_id') or
-                                  cls.client.tenant_id)
+                                  cls.client.project_id)
                     kwargs.update(project_id=project_id, tenant_id=project_id)
             else:
                 # Use default client