Build: Bump undici and release-it

Bumps [undici](https://github.com/nodejs/undici) to 6.21.2 and updates ancestor dependency [release-it](https://github.com/release-it/release-it). These dependencies need to be updated together.

Closes gh-253

Updates `undici` from 6.21.1 to 6.21.2
- [Release notes](https://github.com/nodejs/undici/releases)
- [Commits](nodejs/undici@v6.21.1...v6.21.2)

Updates `release-it` from 18.1.2 to 19.0.2
- [Release notes](https://github.com/release-it/release-it/releases)
- [Changelog](https://github.com/release-it/release-it/blob/main/CHANGELOG.md)
- [Commits](release-it/release-it@18.1.2...19.0.2)

---
updated-dependencies:
- dependency-name: undici
  dependency-version: 6.21.2
  dependency-type: indirect
- dependency-name: release-it
  dependency-version: 19.0.2
  dependency-type: direct:development
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]