Bump the majordependencies group across 1 directory with 2 updates

Bumps the majordependencies group with 2 updates in the /functions directory: [firebase-admin](https://github.com/firebase/firebase-admin-node) and [firebase-functions](https://github.com/firebase/firebase-functions).


Updates `firebase-admin` from 12.5.0 to 13.1.0
- [Release notes](https://github.com/firebase/firebase-admin-node/releases)
- [Changelog](https://github.com/firebase/firebase-admin-node/blob/master/CHANGELOG.md)
- [Commits](firebase/firebase-admin-node@v12.5.0...v13.1.0)

Updates `firebase-functions` from 5.1.1 to 6.3.1
- [Release notes](https://github.com/firebase/firebase-functions/releases)
- [Changelog](https://github.com/firebase/firebase-functions/blob/master/tsconfig.release.json)
- [Commits](firebase/firebase-functions@v5.1.1...v6.3.1)

---
updated-dependencies:
- dependency-name: firebase-admin
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: majordependencies
- dependency-name: firebase-functions
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: majordependencies
...

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