build(deps): bump undici and @rdfjs/serializer-jsonld-ext

Bumps [undici](https://github.com/nodejs/undici) and [@rdfjs/serializer-jsonld-ext](https://github.com/rdfjs-base/serializer-jsonld-ext). These dependencies needed to be updated together.

Updates `undici` from 5.29.0 to 6.24.1
- [Release notes](https://github.com/nodejs/undici/releases)
- [Commits](nodejs/undici@v5.29.0...v6.24.1)

Updates `@rdfjs/serializer-jsonld-ext` from 4.0.0 to 4.0.2
- [Commits](rdfjs-base/serializer-jsonld-ext@v4.0.0...v4.0.2)

---
updated-dependencies:
- dependency-name: undici
  dependency-version: 6.24.1
  dependency-type: indirect
- dependency-name: "@rdfjs/serializer-jsonld-ext"
  dependency-version: 4.0.2
  dependency-type: indirect
...

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Author: dependabot[bot]