Bump furo from 2024.1.29 to 2024.5.6 in /requirements (#47)

Bumps [furo](https://github.com/pradyunsg/furo) from 2024.1.29 to 2024.5.6.
- [Release notes](https://github.com/pradyunsg/furo/releases)
- [Changelog](https://github.com/pradyunsg/furo/blob/main/docs/changelog.md)
- [Commits](pradyunsg/furo@2024.01.29...2024.05.06)

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

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

Author: dependabot[bot]

requirements/docs.txt

@@ -1,7 +1,7 @@
 sphinx~=7.2.6
 sphinx-autobuild==2021.3.14
 sphinx-copybutton~=0.5.2
-furo==2024.1.29
+furo==2024.5.6
 enum-tools[sphinx]~=0.12.0
 sphinx-design[furo]~=0.5.0
 readthedocs-sphinx-search~=0.3.2