deps(book): update lxml requirement from >=5.0.0 to >=6.1.0 (#1458)

Updates the requirements on [lxml](https://github.com/lxml/lxml) to permit the latest version.
- [Release notes](https://github.com/lxml/lxml/releases)
- [Changelog](https://github.com/lxml/lxml/blob/master/CHANGES.txt)
- [Commits](lxml/lxml@lxml-5.0.0...lxml-6.1.0)

---
updated-dependencies:
- dependency-name: lxml
  dependency-version: 6.1.0
  dependency-type: direct:production
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

book/tools/dependencies/requirements.txt

@@ -38,7 +38,7 @@ black>=24.0.0
 #scikit-learn>=1.3.2
 #torch>=2.0.0
 pint>=0.23
-lxml>=5.0.0
+lxml>=6.1.0
 
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 # These are imported by hooks/scripts that pre-commit runs. Without them,