Update sphinx to 4.1.2

[pyup-bot]

This PR updates Sphinx from 4.1.0 to 4.1.2.

Changelog

4.1.2

=====================================

Incompatible changes
--------------------

* 9435: linkcheck: Disable checking automatically generated anchors on
github.com (ex. anchors in reST/Markdown documents)

Bugs fixed
----------

* 9489: autodoc: Custom types using ``typing.NewType`` are not displayed well
with the HEAD of 3.10
* 9490: autodoc: Some objects under ``typing`` module are not displayed well
with the HEAD of 3.10
* 9436, 9471: autodoc: crashed if ``autodoc_class_signature = "separated"``
* 9456: html search: html_copy_source can't control the search summaries
* 9435: linkcheck: Failed to check anchors in github.com

4.1.1

=====================================

Dependencies
------------

* 9434: sphinxcontrib-htmlhelp-2.0.0 or above
* 9434: sphinxcontrib-serializinghtml-1.1.5 or above

Bugs fixed
----------

* 9438: html: HTML logo or Favicon specified as file not being found on output

Links

• PyPI: https://pypi.org/project/sphinx
• Changelog: https://pyup.io/changelogs/sphinx/
• Homepage: https://sphinx-doc.org/

[pyup-bot]

Closing this in favor of #362