deps: update dependency lxml to v5.3.1 (#3624)

This PR contains the following updates:

| Package | Change | Age | Adoption | Passing | Confidence |
|---|---|---|---|---|---|
| [lxml](https://lxml.de/)
([source](https://github.com/lxml/lxml),
[changelog](https://git.launchpad.net/lxml/plain/CHANGES.txt)) |
`==5.3.0` -> `==5.3.1` |
[![age](https://developer.mend.io/api/mc/badges/age/pypi/lxml/5.3.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![adoption](https://developer.mend.io/api/mc/badges/adoption/pypi/lxml/5.3.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![passing](https://developer.mend.io/api/mc/badges/compatibility/pypi/lxml/5.3.0/5.3.1?slim=true)](https://docs.renovatebot.com/merge-confidence/)
|
[![confidence](https://developer.mend.io/api/mc/badges/confidence/pypi/lxml/5.3.0/5.3.1?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>

###
[`v5.3.1`](https://github.com/lxml/lxml/blob/HEAD/CHANGES.txt#531-2025-02-09)

[Compare
Source](https://github.com/lxml/lxml/compare/lxml-5.3.0...lxml-5.3.1)

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

## Bugs fixed

- [GH#440](https://github.com/GH/lxml/issues/440): Some tests
were adapted for libxml2 2.14.0.
    Patch by Nick Wellnhofer.

- [LP#2097175](https://github.com/LP/lxml/issues/2097175):
`DTD(external_id="…")` erroneously required a byte string as ID value.

- [GH#450](https://github.com/GH/lxml/issues/450):
`iterparse()` internally triggered the \`DeprecationWarning\`\` added in
lxml 5.3.0 when parsing HTML.

## Other changes

- [GH#442](https://github.com/GH/lxml/issues/442): Binary
wheels for macOS no longer use the linker flag `-flat_namespace`.

</details>

---

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