Bump systeminformation from 5.17.12 to 5.21.8 in /ui-tests (#1398)

Bumps [systeminformation](https://github.com/sebhildebrandt/systeminformation) from 5.17.12 to 5.21.8.
- [Changelog](https://github.com/sebhildebrandt/systeminformation/blob/master/CHANGELOG.md)
- [Commits](sebhildebrandt/systeminformation@v5.17.12...v5.21.8)

---
updated-dependencies:
- dependency-name: systeminformation
  dependency-type: indirect
...

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