Improve classes and modules docstring

[hussein-awala]

Body

I have observed that the Python API documentation on the Airflow website lacks information about deprecation and the corresponding replacement modules or classes. In many cases, users are only alerted about these changes through log warnings.

The purpose of this task is to enhance the docstrings, focusing particularly on utilizing the Sphinx cross-referencing syntax to improve the documentation.

For example: Not documented deprecation: https://airflow.apache.org/docs/apache-airflow-providers-cncf-kubernetes/stable/_api/airflow/providers/cncf/kubernetes/operators/kubernetes_pod/index.html Documented deprecation: https://airflow.apache.org/docs/apache-airflow-providers-slack/stable/_api/airflow/providers/slack/notifications/slack_notifier/index.html

Add deprecation docstring for:

• [ ] Airflow core modules and classes
• [x] Airflow providers modules and classes
• [ ] Airflow core methods
• [ ] Airflow providers methods

Committer

• [X] I acknowledge that I am a maintainer/committer of the Apache Airflow project.

[NewtonChutney]

The purpose of this task is to enhance the docstrings, focusing particularly on utilizing the Sphinx cross-referencing syntax to improve the documentation.

I'm sadly bringing to your notice that VSCode doesn't render Sphinx syntax properly.. Please do put a notice until VSCode fixes this, that users are to check the docstring in the source code or refer to the Airflow documentation about deprecation. https://github.com/microsoft/pylance-release/issues/5431