Bump testsuite/rdf-star from a7d7db1 to 59eb029

Bumps [testsuite/rdf-star](https://github.com/w3c/rdf-star) from `a7d7db1` to `59eb029`.
- [Commits](w3c/rdf-star@a7d7db1...59eb029)

---
updated-dependencies:
- dependency-name: testsuite/rdf-star
  dependency-type: direct:production
...

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