Bump sphinx-copybutton from 0.5.1 to 0.5.2 in /docs (#3651)

Bumps [sphinx-copybutton](https://github.com/executablebooks/sphinx-copybutton) from 0.5.1 to 0.5.2.
- [Release notes](https://github.com/executablebooks/sphinx-copybutton/releases)
- [Changelog](https://github.com/executablebooks/sphinx-copybutton/blob/master/CHANGELOG.md)
- [Commits](https://github.com/executablebooks/sphinx-copybutton/compare/v0.5.1...v0.5.2

)

---
updated-dependencies:
- dependency-name: sphinx-copybutton
  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>