Bump ext/Avalonia from 6dd9eb4 to 4e30256 (#50)

Bumps [ext/Avalonia](https://github.com/AvaloniaUI/Avalonia) from `6dd9eb4` to `4e30256`.
- [Release notes](https://github.com/AvaloniaUI/Avalonia/releases)
- [Commits](AvaloniaUI/Avalonia@6dd9eb4...4e30256)

---
updated-dependencies:
- dependency-name: ext/Avalonia
  dependency-version: 4e302560fc9f84de1fe64360e29165574cf2ea65
  dependency-type: direct:production
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]