Bump xo from 2.0.2 to 4.0.0

Bumps [xo](https://github.com/xojs/xo) from 2.0.2 to 4.0.0.
- [Release notes](https://github.com/xojs/xo/releases)
- [Commits](xojs/xo@v2.0.2...v4.0.0)

---
updated-dependencies:
- dependency-name: xo
  dependency-version: 4.0.0
  dependency-type: direct:development
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]