feat(tracing): update OCI Generative AI tracing notebook and remove examples

- Refactored the `oci_genai_tracing.ipynb` notebook to enhance clarity and organization, including a new setup section for Openlayer API key and inference pipeline ID.
- Removed the `README.md` and `simple_oci_example.py` files as they are no longer needed, consolidating documentation within the notebook.
- Improved the structure of the notebook by replacing raw cells with markdown cells for better readability and user experience.
- Ensured all changes comply with coding standards, including comprehensive type annotations and Google-style docstrings for maintainability.

Author: viniciusdsmello