[Python] Add recipe for appending/replacing data set partitions

The pyarrow [docs](https://arrow.apache.org/docs/python/generated/pyarrow.dataset.write_dataset.html#pyarrow.dataset.write_dataset) for the `exisiting_data_behavior` param contains this hint:

> This behavior, in combination with a unique basename_template for each write, will allow for an append workflow.
>
>‘delete_matching’ is useful when you are writing a partitioned dataset. The first time each partition directory is encountered the entire directory will be deleted. This allows you to overwrite old partitions completely.

A fully formed recipe for this would be nice as this hint is a bit hidden.

The issue points to pyarrow.dataset.write_dataset and its existing_data_behavior parameter; start by reading that API documentation and the append and delete_matching hints. Add a cookbook recipe covering appending and replacing partitioned data, with examples that make the completed workflows clear.

Written by the indexing model from the issue text.