No new documentation for breaking feature store changes in 3.0.1

Version 3.0.1 was recently released, with breaking changes (apparent removal of the `sagemaker.feature_store` module) for feature store.

The [Python SDK documentation](https://sagemaker.readthedocs.io/en/stable/) has not been updated to include documentation for version 3.0.1.

The README suggests checking out the v3-examples folder for "documentation," but there are no examples for interacting with feature store objects.

Don't y'all think it might be helpful to show users how to use this new thing you built?

首先，查看 v3-examples 文件夹的 README 指南，以及当前针对 3.0.1 版本和 feature store 支持的 Python SDK 文档。完成的标准是文档反映 breaking changes，并且 v3-examples 文件夹包含展示如何与 feature store 对象交互的示例。

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