Bump flutter_lints from 2.0.3 to 3.0.0 in /google-maps-in-flutter/step_4

Bumps [flutter_lints](https://github.com/flutter/packages/tree/main/packages) from 2.0.3 to 3.0.0.
- [Release notes](https://github.com/flutter/packages/releases)
- [Commits](https://github.com/flutter/packages/commits/pigeon-v3.0.0/packages)

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

Signed-off-by: dependabot[bot] <support@github.com>

google-maps-in-flutter/step_4/pubspec.yaml

@@ -46,7 +46,7 @@ dev_dependencies:
   # activated in the `analysis_options.yaml` file located at the root of your
   # package. See that file for information about deactivating specific lint
   # rules and activating additional ones.
-  flutter_lints: ^2.0.0
+  flutter_lints: ^3.0.0
 
 # For information on the generic Dart part of this file, see the
 # following page: https://dart.dev/tools/pub/pubspec