build(deps): bump third_party/tools/synlig from f5cd191 to 2d838ed

Bumps [third_party/tools/synlig](https://github.com/chipsalliance/synlig) from `f5cd191` to `2d838ed`.
- [Release notes](https://github.com/chipsalliance/synlig/releases)
- [Commits](chipsalliance/synlig@f5cd191...2d838ed)

---
updated-dependencies:
- dependency-name: third_party/tools/synlig
  dependency-type: direct:production
...

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