Bumps [syn](https://github.com/dtolnay/syn) from 1.0.31 to 1.0.35.
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](dtolnay/syn@1.0.31...1.0.35)

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