[ADD] padding to demo

Signed-off-by: Jonas Klock <jonas.klock@exxeta.com>

Author: jay-k98

example/lib/presentation/samples/stacked_pie/stacked_pie_chart_sample1.dart

@@ -12,16 +12,14 @@ class _StackedPieChartSample1State extends State<StackedPieChartSample1> {
   @override
   Widget build(BuildContext context) {
     return const AspectRatio(
-      aspectRatio: 1.3,
+      aspectRatio: 1.0,
       child: Column(
         children: <Widget>[
           SizedBox(height: 28),
           Expanded(
-            child: AspectRatio(
-              aspectRatio: 1,
-              child: StackedPieDemo(),
-            ),
+            child: StackedPieDemo(),
           ),
+          SizedBox(height: 28),
         ],
       ),
     );

lib/src/chart/stacked_pie_chart/stacked_pie_chart_data.dart

@@ -32,7 +32,7 @@ class StackedPieChartData extends BaseChartData with EquatableMixin {
     FlBorderData? borderData,
     bool? titleSunbeamLayout,
   })  : sections = sections ?? const [],
-        centerSpaceRadius = centerSpaceRadius ?? double.infinity,
+        centerSpaceRadius = centerSpaceRadius ?? 16,
         centerSpaceColor = centerSpaceColor ?? Colors.transparent,
         sectionsSpace = sectionsSpace ?? 2,
         startDegreeOffset = startDegreeOffset ?? 0,