[deps]: Update Rust crate validator to >=0.18.1, <0.21 (#247)

This PR contains the following updates:

| Package | Type | Update | Change |
|---|---|---|---|
| [validator](https://redirect.github.com/Keats/validator) |
workspace.dependencies | minor | `>=0.18.1, <0.20` -> `>=0.18.1, <0.21`
|

---

### Release Notes

<details>
<summary>Keats/validator (validator)</summary>

###
[`v0.20.0`](https://redirect.github.com/Keats/validator/blob/HEAD/CHANGELOG.md#0200-20250120)

-   Implement `AsRegex` for `std::sync::LazyLock<Regex>`
- Bug fix for nested issue with custom only running nested if outer
passes
-   Support `Deserialize` for `ValidationErrors`

</details>

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Cargo.lock

@@ -66,7 +66,7 @@ tsify-next = { version = ">=0.5.4, <0.6", features = [
 ], default-features = false }
 uniffi = "=0.29.1"
 uuid = { version = ">=1.3.3, <2.0", features = ["serde", "v4", "js"] }
-validator = { version = ">=0.18.1, <0.20", features = ["derive"] }
+validator = { version = ">=0.18.1, <0.21", features = ["derive"] }
 wasm-bindgen = { version = ">=0.2.91, <0.3", features = ["serde-serialize"] }
 wasm-bindgen-futures = "0.4.41"
 wasm-bindgen-test = "0.3.45"