Update lxml to 5.3.0

[pyup-bot]

This PR updates lxml from 5.2.2 to 5.3.0.

Changelog

5.3.0

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

Features added
--------------

* GH421: Nested ``CDATA`` sections are no longer rejected but split on output
to represent ``]]>`` correctly.
Patch by Gertjan Klein.

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

* LP2060160: Attribute values serialised differently in ``xmlfile.element()`` and ``xmlfile.write()``.

* LP2058177: The ISO-Schematron implementation could fail on unknown prefixes.
Patch by David Lakin.

Other changes
-------------

* LP2067707: The ``strip_cdata`` option in ``HTMLParser()`` turned out to be useless and is now deprecated.

* Binary wheels use the library versions libxml2 2.12.9 and libxslt 1.1.42.

* Windows binary wheels use the library versions libxml2 2.11.8 and libxslt 1.1.39.

* Built with Cython 3.0.11.

Links

• PyPI: https://pypi.org/project/lxml
• Changelog: https://data.safetycli.com/changelogs/lxml/
• Homepage: https://lxml.de/