build(deps): bump nunjucks and dgeni-packages

Bumps [nunjucks](https://github.com/mozilla/nunjucks) to 3.2.4 and updates ancestor dependency [dgeni-packages](https://github.com/angular/dgeni-packages). These dependencies need to be updated together.


Updates `nunjucks` from 2.5.2 to 3.2.4
- [Release notes](https://github.com/mozilla/nunjucks/releases)
- [Changelog](https://github.com/mozilla/nunjucks/blob/master/CHANGELOG.md)
- [Commits](mozilla/nunjucks@v2.5.2...v3.2.4)

Updates `dgeni-packages` from 0.16.10 to 0.30.0
- [Release notes](https://github.com/angular/dgeni-packages/releases)
- [Changelog](https://github.com/angular/dgeni-packages/blob/master/CHANGELOG.md)
- [Commits](angular/dgeni-packages@v0.16.10...v0.30.0)

---
updated-dependencies:
- dependency-name: nunjucks
  dependency-type: indirect
- dependency-name: dgeni-packages
  dependency-type: direct:development
...

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