[Python] [Docs] Mention the C Data/Stream Interface in PyArrow Extending

The [Arrow C Data/Stream Interface](https://arrow.apache.org/docs/format/CDataInterface.html) is a relatively lightweight option for developers that want to expose Arrow Arrays to Python users.

It is not mentioned as a recommendation in the documentation on [using pyarrow from C++ code\|[https://arrow.apache.org/docs/python/integration/extending.html].]

The existing recommendation mentioned is [wrapping and unwrapping\|[https://arrow.apache.org/docs/python/integration/extending.html#wrapping-and-unwrapping].]

I propose adding a section to this page. I would be happy to take that on, if others agree that is a good idea.

**Reporter**: [Anja Boskovic](https://issues.apache.org/jira/browse/ARROW-18404) / @anjakefala
**Assignee**: [Anja Boskovic](https://issues.apache.org/jira/browse/ARROW-18404) / @anjakefala

_{**Note**: *This issue was originally created as [ARROW-18404](https://issues.apache.org/jira/browse/ARROW-18404). Please see the [migration documentation](https://github.com/apache/arrow/issues/14542) for further details.*}

Start with docs/python/integration/extending.html, especially the existing “wrapping and unwrapping” section, and read the linked Arrow C Data/Stream Interface documentation. Add a section recommending the interface for exposing Arrow Arrays to Python users, with scope and wording consistent with the page.

Written by the indexing model from the issue text.