deps: update dependency lxml to v5.3.0 (#3237)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [lxml](https://lxml.de/)
([source](https://redirect.github.com/lxml/lxml),
[changelog](https://git.launchpad.net/lxml/plain/CHANGES.txt)) |
`==5.2.2` -> `==5.3.0` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/lxml/5.3.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/pypi/lxml/5.3.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/pypi/lxml/5.2.2/5.3.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/lxml/5.2.2/5.3.0?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|

---

> [!WARNING]
> Some dependencies could not be looked up. Check the Dependency
Dashboard for more information.

---

### Release Notes

<details>
<summary>lxml/lxml (lxml)</summary>

###
[`v5.3.0`](https://redirect.github.com/lxml/lxml/blob/HEAD/CHANGES.txt#530-2024-08-10)

[Compare
Source](https://redirect.github.com/lxml/lxml/compare/lxml-5.2.2...lxml-5.3.0)

\==================

## Features added

- [GH#421](https://redirect.github.com/GH/lxml/issues/421): Nested
`CDATA` sections are no longer rejected but split on output
    to represent `]]>` correctly.
    Patch by Gertjan Klein.

## Bugs fixed

- [LP#2060160](https://redirect.github.com/LP/lxml/issues/2060160):
Attribute values serialised differently in `xmlfile.element()` and
`xmlfile.write()`.

- [LP#2058177](https://redirect.github.com/LP/lxml/issues/2058177): The
ISO-Schematron implementation could fail on unknown prefixes.
    Patch by David Lakin.

## Other changes

- [LP#2067707](https://redirect.github.com/LP/lxml/issues/2067707): 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.

</details>

---

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