build(deps): bump python-levenshtein in /lib/spack/docs (#38339)

Bumps [python-levenshtein](https://github.com/maxbachmann/python-Levenshtein) from 0.21.0 to 0.21.1.
- [Release notes](https://github.com/maxbachmann/python-Levenshtein/releases)
- [Changelog](https://github.com/maxbachmann/python-Levenshtein/blob/main/HISTORY.md)
- [Commits](https://github.com/maxbachmann/python-Levenshtein/compare/v0.21.0...v0.21.1)

---
updated-dependencies:
- dependency-name: python-levenshtein
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

lib/spack/docs/requirements.txt

@@ -2,7 +2,7 @@ sphinx==6.2.1
 sphinxcontrib-programoutput==0.17
 sphinx_design==0.4.1
 sphinx-rtd-theme==1.2.2
-python-levenshtein==0.21.0
+python-levenshtein==0.21.1
 docutils==0.18.1
 pygments==2.15.1
 urllib3==2.0.3