chore(deps-dev): bump pack-n-play from 2.0.1 to 5.1.0

Bumps [pack-n-play](https://github.com/googleapis/google-cloud-node/tree/HEAD/core/dev-packages/pack-n-play) from 2.0.1 to 5.1.0.
- [Release notes](https://github.com/googleapis/google-cloud-node/releases)
- [Changelog](https://github.com/googleapis/google-cloud-node/blob/main/core/dev-packages/pack-n-play/CHANGELOG.md)
- [Commits](https://github.com/googleapis/google-cloud-node/commits/pack-n-play-v5.1.0/core/dev-packages/pack-n-play)

---
updated-dependencies:
- dependency-name: pack-n-play
  dependency-version: 5.1.0
  dependency-type: direct:development
  update-type: version-update:semver-major
...

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Author: dependabot[bot]