Bump lxml from 4.9.3 to 5.2.2 in /backend

Bumps [lxml](https://github.com/lxml/lxml) from 4.9.3 to 5.2.2.
- [Release notes](https://github.com/lxml/lxml/releases)
- [Changelog](https://github.com/lxml/lxml/blob/master/CHANGES.txt)
- [Commits](lxml/lxml@lxml-4.9.3...lxml-5.2.2)

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

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