Bump urijs from 1.19.7 to 1.19.8 in /tests/unit_tests
    
    Bumps [urijs](https://github.com/medialize/URI.js) from 1.19.7 to 1.19.8.
    - [Release notes](https://github.com/medialize/URI.js/releases)
    - [Changelog](https://github.com/medialize/URI.js/blob/gh-pages/CHANGELOG.md)
    - [Commits](https://github.com/medialize/URI.js/compare/v1.19.7...v1.19.8)
    
    ---
    updated-dependencies:
    - dependency-name: urijs
      dependency-type: indirect
    ...
    
    Signed-off-by: dependabot[bot] <support@github.com>