build(deps): bump undici in /playgrounds (#2123)

Bumps  and [undici](https://github.com/nodejs/undici). These dependencies needed to be updated together.

Updates `undici` from 7.27.2 to 7.28.0
- [Release notes](https://github.com/nodejs/undici/releases)
- [Commits](nodejs/undici@v7.27.2...v7.28.0)

Updates `undici` from 6.26.0 to 6.27.0
- [Release notes](https://github.com/nodejs/undici/releases)
- [Commits](nodejs/undici@v7.27.2...v7.28.0)

---
updated-dependencies:
- dependency-name: undici
  dependency-version: 7.28.0
  dependency-type: indirect
- dependency-name: undici
  dependency-version: 6.27.0
  dependency-type: indirect
...

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Author: dependabot[bot]