Bump gson from 2.3 to 2.8.9

Bump gson from 2.3 to 2.8.9

Bumps [gson](https://github.com/google/gson) from 2.3 to 2.8.9.
- [Release notes](https://github.com/google/gson/releases)
- [Changelog](https://github.com/google/gson/blob/master/CHANGELOG.md)
- [Commits](https://github.com/google/gson/compare/gson-2.3...gson-parent-2.8.9)

---
updated-dependencies:
- dependency-name: com.google.code.gson:gson
  dependency-type: direct:production
...

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