Support dart 2.17

[MegatronKing]

Flutter has upgraded dart to 2.17, throws some error in generating if the project uses 'super-parameters' language feature.

This builder requires Dart inputs without syntax errors.
However, package:reqable/framework/widgets.dart (or an existing part) contains the following errors.
resize.dart:13:5: This requires the 'super-parameters' language feature to be enabled.
reorderable.dart:21:5: This requires the 'super-parameters' language feature to be enabled.
reorderable.dart:422:5: This requires the 'super-parameters' language feature to be enabled.

Try fixing the errors and re-running the build.

[greenrobot-team]

Thanks for reporting. However, does this really require an update to the objectbox package? Is it not enough to increase the minimum sdk version of your package/app? https://stackoverflow.com/questions/72197622/this-requires-the-super-parameters-language-feature-to-be-enabled

[MegatronKing]

@greenrobot-team Thanks for reply. Upgrade min sdk version does not work, I found a workaround from dart-lang/language#1855
Using the following cli to generate objectbox.g.dart:

flutter pub run build_runner build serve --enable-experiment=super-parameters