Bump third_party/jsoncpp/repo from 42e892d to 69098a1 (#28036)

Bumps [third_party/jsoncpp/repo](https://github.com/open-source-parsers/jsoncpp) from `42e892d` to `69098a1`.
- [Release notes](https://github.com/open-source-parsers/jsoncpp/releases)
- [Commits](open-source-parsers/jsoncpp@42e892d...69098a1)

---
updated-dependencies:
- dependency-name: third_party/jsoncpp/repo
  dependency-type: direct:production
...

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