Bump prospector from 1.5.3.1 to 1.6.0

Bumps [prospector](https://github.com/PyCQA/prospector) from 1.5.3.1 to 1.6.0.
- [Release notes](https://github.com/PyCQA/prospector/releases)
- [Changelog](https://github.com/PyCQA/prospector/blob/master/CHANGELOG.rst)
- [Commits](https://github.com/PyCQA/prospector/compare/1.5.3.1...1.6.0)

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

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