[BUG] an empty file \lib\swagger_dart_code_generator_temp.dart remains after successful build

[dJani97]

Describe the bug
An empty file \lib\swagger_dart_code_generator_temp.dart is left behind after each build. I don't recall having this problem in earlier versions, but I don't know exactly when it got introduced.

To Reproduce

git clone https://github.com/epam-cross-platform-lab/swagger-dart-code-generator
cd .\swagger-dart-code-generator\example
flutter pub get
flutter packages pub run build_runner build --delete-conflicting-outputs

Expected behavior
I would expect temp files to be deleted, or be used outside of the /lib folder.
I also suggest removing this file not only in case of success, but also in case of a build failure.

Library version used (latest of everything, as of today):
OS: Windows 11
Flutter 2.10.2 • channel stable
swagger_dart_code_generator: ^2.4.2
chopper_generator: ^4.0.5
json_annotation: ^4.4.0
json_serializable: ^6.1.4

[Vovanella95]

Fixed here: #353