Add a guide for MLflow observability integration with Anthropic

[TomeHirata]

Hi, team. I'm a core maintainer of MLFlow, one of the most popular tools for ML workflow management.
We have recently introduced a new tracing integration with the Anthropic Python ADK and we would be grateful if we could add a guide for the integration to this Cookbook. The guide will include example codes for using the MLflow tracing integration and links to the relevant documentation.
Please refer to https://mlflow.org/docs/latest/llms/tracing/index.html for the tracing integration.