Docs: don't render files in includes/, they're for embedding only

[hugovk]

Before

1. Go to https://docs.python.org/3.12/ and search for wasi
2. https://docs.python.org/3.12/search.html?q=wasi shows a <no title> page first:

3. Click <no title>, it shows https://docs.python.org/3/includes/wasm-notavail.html?highlight=wasi:

That's https://github.com/python/cpython/blob/main/Doc/includes/wasm-notavail.rst which is not meant to be rendered as a standalone page.

Instead it is meant to be embedded into pages via:

.. include:: ../includes/wasm-notavail.rst

For example:

• https://docs.python.org/3/library/venv.html?highlight=wasi
• https://raw.githubusercontent.com/python/cpython/3.11/Doc/library/venv.rst

So let's exclude files in includes/ from being rendered individually by adding it to exclude_patterns.

• https://www.sphinx-doc.org/en/master/usage/configuration.html#confval-exclude_patterns

After

1. Go to https://deploy-preview-103313--python-cpython-preview.netlify.app/ and search for wasi
2. https://deploy-preview-103313--python-cpython-preview.netlify.app/search.html?q=wasi&check_keywords=yes&area=default shows a <no title> page first:

3. There is no <no title> result and there is no standalone https://deploy-preview-103313--python-cpython-preview.netlify.app/includes/wasm-notavail.html?highlight=wasi

4. The include is still embedded on pages such as https://deploy-preview-103313--python-cpython-preview.netlify.app/library/venv.html?highlight=wasi

[miss-islington]

Thanks @hugovk for the PR 🌮🎉.. I'm working now to backport this PR to: 3.11.
🐍🍒⛏🤖

[bedevere-bot]

GH-103433 is a backport of this pull request to the 3.11 branch.