deps: update rust crate syn to v2.0.65

[renovate[bot]]

This PR contains the following updates:

Package	Type	Update	Change
syn	dependencies	patch	2.0.64 -> 2.0.65

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Release Notes

dtolnay/syn (syn)

### [`v2.0.65`](https://togithub.com/dtolnay/syn/releases/tag/2.0.65) [Compare Source](https://togithub.com/dtolnay/syn/compare/2.0.64...2.0.65) - Optimize the implementation of `Fold` to compile faster ([#​1666](https://togithub.com/dtolnay/syn/issues/1666), [#​1667](https://togithub.com/dtolnay/syn/issues/1667), [#​1668](https://togithub.com/dtolnay/syn/issues/1668))

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