Upgrade sqlx dependency to 0.9

The latest version of sqlx is now 0.9. I'd recommend upgrading from the current version to 0.9, as this can help prevent version conflicts with other popular crates, such as sea-orm v2, which already depends on sqlx 0.9 🙏

Locate the sqlx dependency in the repository's Cargo manifests and check the current version and related lockfile entries. Update it to 0.9, then run the existing Rust test or build commands; done means the dependency resolves successfully without the reported version conflict.

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