build(deps): bump blessed from 1.19.1 to 1.20.0

Bumps [blessed](https://github.com/jquast/blessed) from 1.19.1 to 1.20.0.
- [Release notes](https://github.com/jquast/blessed/releases)
- [Changelog](https://github.com/jquast/blessed/blob/master/docs/history.rst)
- [Commits](jquast/blessed@1.19.1...1.20.0)

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

Signed-off-by: dependabot[bot] <[email protected]>