chore(deps): update rust crate syn to v2.0.73 (#306)

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This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [syn](https://togithub.com/dtolnay/syn) | workspace.dependencies | patch | `2.0.72` -> `2.0.73` |

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### Release Notes

<details>
<summary>dtolnay/syn (syn)</summary>

### [`v2.0.73`](https://togithub.com/dtolnay/syn/releases/tag/2.0.73)

[Compare Source](https://togithub.com/dtolnay/syn/compare/2.0.72...2.0.73)

-   Support parsing unnamed C varargs within function pointer types ([#&#8203;1711](https://togithub.com/dtolnay/syn/issues/1711))
-   Improve synthesized error message on unexpected tokens at the end of the expected contents of a delimited group ([#&#8203;1713](https://togithub.com/dtolnay/syn/issues/1713))
-   Support parsing unstable tail call syntax ([#&#8203;1714](https://togithub.com/dtolnay/syn/issues/1714), [https://github.com/rust-lang/rust/issues/112788](https://togithub.com/rust-lang/rust/issues/112788))
-   Add [`Fields::members`](https://docs.rs/syn/2.0.73/syn/enum.Fields.html#method.members) iterator ([#&#8203;1716](https://togithub.com/dtolnay/syn/issues/1716), thanks [@&#8203;Fancyflame](https://togithub.com/Fancyflame))

</details>

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