Upgrade flutter_lints version to 6.0.0 in example/

Author: imaNNeo

example/lib/presentation/samples/line/line_chart_sample11.dart

@@ -72,7 +72,7 @@ class _Chart extends StatelessWidget {
 
   const _Chart(this.baselineX, this.baselineY) : super();
 
-  Widget getHorizontalTitles(value, TitleMeta meta) {
+  Widget getHorizontalTitles(double value, TitleMeta meta) {
     TextStyle style;
     if ((value - baselineX).abs() <= 0.1) {
       style = const TextStyle(
@@ -92,7 +92,7 @@ class _Chart extends StatelessWidget {
     );
   }
 
-  Widget getVerticalTitles(value, TitleMeta meta) {
+  Widget getVerticalTitles(double value, TitleMeta meta) {
     TextStyle style;
     if ((value - baselineY).abs() <= 0.1) {
       style = const TextStyle(

example/lib/presentation/samples/line/line_chart_sample13.dart

@@ -324,7 +324,7 @@ class _LineChartSample13State extends State<LineChartSample13> {
     );
   }
 
-  _touchCallback(FlTouchEvent event, LineTouchResponse? touchResponse) {
+  void _touchCallback(FlTouchEvent event, LineTouchResponse? touchResponse) {
     if (!event.isInterestedForInteractions ||
         touchResponse?.lineBarSpots == null ||
         touchResponse!.lineBarSpots!.isEmpty) {

example/pubspec.yaml

@@ -28,7 +28,7 @@ dependencies:
 dev_dependencies:
   flutter_test:
     sdk: flutter
-  flutter_lints: ^4.0.0
+  flutter_lints: ^6.0.0
 
 flutter:
   uses-material-design: true