Add cut-off date for Duo Enterprise AI proxy features

- Set cut-off date to 2024-10-17 00:00:00 UTC for anthropic_proxy and vertex_ai_proxy
- Updated both config/cloud_connector.yml and ee/config/cloud_connector/access_data.yml
- Ensures these features will require Duo Enterprise license after the cut-off date
- Part of the initiative to end free access for all Duo features