Bump lxml from 5.1.0 to 5.3.0

Bumps [lxml](https://github.com/lxml/lxml) from 5.1.0 to 5.3.0.
- [Release notes](https://github.com/lxml/lxml/releases)
- [Changelog](https://github.com/lxml/lxml/blob/master/CHANGES.txt)
- [Commits](https://github.com/lxml/lxml/compare/lxml-5.1.0...lxml-5.3.0)

---
updated-dependencies:
- dependency-name: lxml
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <support@github.com>

requirements.txt

@@ -11,7 +11,7 @@ django-oauth-toolkit==2.4.0
 django-debug-toolbar==4.3.0
 bleach==6.0.0
 gunicorn==22.0.0
-lxml==5.1.0
+lxml==5.3.0
 Markdown==3.5.1
 Pillow==10.4.0
 psycopg2-binary==2.9.9