Bump dart-lang/setup-dart from 1.6.4 to 1.6.5 (#241)

Bumps [dart-lang/setup-dart](https://github.com/dart-lang/setup-dart) from 1.6.4 to 1.6.5.
- [Release notes](https://github.com/dart-lang/setup-dart/releases)
- [Changelog](https://github.com/dart-lang/setup-dart/blob/main/CHANGELOG.md)
- [Commits](https://github.com/dart-lang/setup-dart/compare/f0ead981b4d9a35b37f30d36160575d60931ec30...0a8a0fc875eb934c15d08629302413c671d3f672)

---
updated-dependencies:
- dependency-name: dart-lang/setup-dart
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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