upgrade: update dependency dart to v3.1.5 (#445)

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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 | `3.1.4` ->
`3.1.5` |

---

### Release Notes

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

###
[`v3.1.5`](https://togithub.com/dart-lang/sdk/blob/HEAD/CHANGELOG.md#315---2023-10-25)

[Compare
Source](https://togithub.com/dart-lang/sdk/compare/3.1.4...3.1.5)

This is a patch release that:

- Fixes an issue affecting Dart compiled to JavaScript running in
Node.js 21. A
change in Node.js 21 affected the Dart Web compiler runtime. This patch
release accomodates for those changes (issue
[#&#8203;53810](https://togithub.com/dart-lang/sdk/issues/53810)).

[#&#8203;53810]: https://togithub.com/dart-lang/sdk/issues/53810

</details>

---

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.tool-versions

@@ -1,2 +1,2 @@
-dart 3.1.4
+dart 3.1.5
 flutter 3.13.8-stable