An issue was observered in adoption CI https://issues.redhat.com/browse/OSPCIX-453 .

As part of adoption we have below scenario

• test vm is created on to be adopted cloud
• neutron is adopted/started before nova adoption(nova endpoints created during nova adoption)
• for some port events, neutron tries to notify nova and due to no nova endpoint it fails
• Even after nova endpoint created the notify event continue to fail until the token(containing service catalog) expire/renew(keystone default token expiration time is 60 minutes, it renews ~ 2minutes before expire)
• If tempest tests involving vm creation runs after the token renewal they pass else fails

We can catch the exception to invalidate the session so it do not have to wait for token expiration after endpoint exists.