build(deps): bump syn from 1.0.68 to 1.0.69 (#672)

Bumps [syn](https://github.com/dtolnay/syn) from 1.0.68 to 1.0.69.
- [Release notes](https://github.com/dtolnay/syn/releases)
- [Commits](dtolnay/syn@1.0.68...1.0.69)

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Shella Stephens <shella@iqlusion.io>