upgrade: update dependency dart to v3.5.4 (#591)

This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [dart](https://dart.dev/)
([source](https://redirect.github.com/dart-lang/sdk)) | patch | `3.5.3`
-> `3.5.4` |

---

### Release Notes

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

###
[`v3.5.4`](https://redirect.github.com/dart-lang/sdk/compare/3.5.3...3.5.4)

[Compare
Source](https://redirect.github.com/dart-lang/sdk/compare/3.5.3...3.5.4)

</details>

---

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.tool-versions

@@ -1,2 +1,2 @@
-dart 3.5.3
+dart 3.5.4
 flutter 3.24.3-stable