chore(deps): Bump the spotify_sdk_example group across 1 directory with 2 updates

Bumps the spotify_sdk_example group with 2 updates in the /example directory: [flutter_dotenv](https://github.com/java-james/flutter_dotenv) and [flutter_lints](https://github.com/flutter/packages/tree/main/packages).


Updates `flutter_dotenv` from 5.2.1 to 6.0.0
- [Changelog](https://github.com/java-james/flutter_dotenv/blob/master/CHANGELOG.md)
- [Commits](https://github.com/java-james/flutter_dotenv/commits)

Updates `flutter_lints` from 5.0.0 to 6.0.0
- [Release notes](https://github.com/flutter/packages/releases)
- [Commits](https://github.com/flutter/packages/commits/flutter_lints-v6.0.0/packages)

---
updated-dependencies:
- dependency-name: flutter_dotenv
  dependency-version: 6.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: spotify_sdk_example
- dependency-name: flutter_lints
  dependency-version: 6.0.0
  dependency-type: direct:production
  update-type: version-update:semver-major
  dependency-group: spotify_sdk_example
...

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

Author: dependabot[bot]

example/pubspec.yaml

@@ -9,7 +9,7 @@ dependencies:
   flutter:
     sdk: flutter
   logger: ^2.4.0
-  flutter_dotenv: ^5.1.0
+  flutter_dotenv: ^6.0.0
   cupertino_icons: ^1.0.8
   spotify_sdk:
     # When depending on this package from a real application you should use:
@@ -22,7 +22,7 @@ dependencies:
 dev_dependencies:
   flutter_test:
     sdk: flutter
-  flutter_lints: ^5.0.0
+  flutter_lints: ^6.0.0
 
 # For information on the generic Dart part of this file, see the
 # following page: https://dart.dev/tools/pub/pubspec