build(deps): bump syn from 2.0.60 to 2.0.63

Bumps [syn](https://github.com/dtolnay/syn) from 2.0.60 to 2.0.63.
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](dtolnay/syn@2.0.60...2.0.63)

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

Signed-off-by: dependabot[bot] <support@github.com>