build(deps): bump lxml from 4.9.4 to 5.1.1

Bumps [lxml](https://github.com/lxml/lxml) from 4.9.4 to 5.1.1.
- [Release notes](https://github.com/lxml/lxml/releases)
- [Changelog](https://github.com/lxml/lxml/blob/master/CHANGES.txt)
- [Commits](lxml/lxml@lxml-4.9.4...lxml-5.1.1)

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

Signed-off-by: dependabot[bot] <[email protected]>

requirements/base.txt

@@ -20,7 +20,7 @@ Pygments==2.17.2
 python-markdown-math==0.6
 
 # XML Parsing
-lxml==4.9.4
+lxml==5.1.1
 cssselect==1.2.0
 
 # YAML Loading