chore(deps-dev): Bump undici

Bumps the npm_and_yarn group with 1 update in the /docs directory: [undici](https://github.com/nodejs/undici).


Updates `undici` from 6.20.1 to 6.21.1
- [Release notes](https://github.com/nodejs/undici/releases)
- [Commits](nodejs/undici@v6.20.1...v6.21.1)

---
updated-dependencies:
- dependency-name: undici
  dependency-type: indirect
  dependency-group: npm_and_yarn
...

Signed-off-by: dependabot[bot] <[email protected]>