Bump xdoctest from 1.1.5 to 1.1.6 (#689)

Bumps [xdoctest](https://github.com/Erotemic/xdoctest) from 1.1.5 to 1.1.6.
- [Release notes](https://github.com/Erotemic/xdoctest/releases)
- [Changelog](https://github.com/Erotemic/xdoctest/blob/main/CHANGELOG.md)
- [Commits](Erotemic/xdoctest@v1.1.5...v1.1.6)

---
updated-dependencies:
- dependency-name: xdoctest
  dependency-type: direct:development
  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>
Co-authored-by: Thibaut Durand <durand.tibo@gmail.com>