deps: bump syn from 2.0.117 to 3.0.2

Bumps [syn](https://github.com/dtolnay/syn) from 2.0.117 to 3.0.2.
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](dtolnay/syn@2.0.117...3.0.2)

---
updated-dependencies:
- dependency-name: syn
  dependency-version: 3.0.2
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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Author: dependabot[bot]