⬆️ Bump lints from 4.0.0 to 5.0.0 in /chopper (#641)

* ⬆️ Bump lints from 4.0.0 to 5.0.0 in /chopper

Bumps [lints](https://github.com/dart-lang/lints) from 4.0.0 to 5.0.0.
- [Release notes](https://github.com/dart-lang/lints/releases)
- [Changelog](https://github.com/dart-lang/lints/blob/main/CHANGELOG.md)
- [Commits](dart-lang/lints@v4.0.0...v5.0.0)

---
updated-dependencies:
- dependency-name: lints
  dependency-type: direct:production
  update-type: version-update:semver-major
...

Signed-off-by: dependabot[bot] <[email protected]>

* 🚨 fix linter warnings

---------

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Klemen Tušar <[email protected]>

chopper/lib/chopper.dart

@@ -1,7 +1,7 @@
 /// Chopper is an http client generator using source_gen and inspired by Retrofit.
 ///
 /// [Getting Started](https://hadrien-lejard.gitbook.io/chopper)
-library chopper;
+library;
 
 export 'package:qs_dart/qs_dart.dart' show ListFormat;
 export 'src/annotations.dart';

chopper/pubspec.yaml

@@ -23,7 +23,7 @@ dev_dependencies:
   data_fixture_dart: ^2.2.0
   faker: ^2.1.0
   http_parser: ^4.0.2
-  lints: ^4.0.0
+  lints: ">=4.0.0 <6.0.0"
   test: ^1.25.5
   transparent_image: ^2.0.1
   chopper_generator: ^8.0.1