upgrade: update dependency dart to v3.3.4 (#506)

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This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [dart](https://dart.dev/)
([source](https://togithub.com/dart-lang/sdk)) | patch | `3.3.3` ->
`3.3.4` |

---

### Release Notes

<details>
<summary>dart-lang/sdk (dart)</summary>

###
[`v3.3.4`](https://togithub.com/dart-lang/sdk/blob/HEAD/CHANGELOG.md#334---2024-04-17)

[Compare
Source](https://togithub.com/dart-lang/sdk/compare/3.3.3...3.3.4)

This is a patch release that:

- Fixes an issue with JS interop in dart2wasm where JS interop methods
that used
the enclosing library's `@JS` annotation were actually using the
invocation's
    enclosing library's `@JS` annotation. (issue [#&#8203;55430]).

[#&#8203;55430]: https://togithub.com/dart-lang/sdk/issues/55430

</details>

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.tool-versions

@@ -1,2 +1,2 @@
-dart 3.3.3
+dart 3.3.4
 flutter 3.19.5-stable