Update building-a-flutter-app.md (#2705)

content/yaml-quick-start/building-a-flutter-app.md

@@ -257,9 +257,9 @@ Please make sure to wrap the `--bundle` pattern in single quotes. If the `--bund
     - build\windows\x64\runner\release.zip
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 🔔 Note: Flutter changed Windows build path to add the target architecture which landed in 3.15.0-0.0.pre and in stable release v3.16.0. More info can be found [here](https://docs.flutter.dev/release/breaking-changes/windows-build-architecture). So, depending on the Flutter version being used, `\x64` needs to be added to the path in order to be able to produce a zip file containing `.exe`
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 #### Creating an MSIX package for publishing to Microsoft Store
 Codemagic uses the [Flutter msix package](https://pub.dev/packages/msix) for packaging the application. For publishing to the Microsoft Store, it is necessary to define certain arguments during packaging.