feat: fix minor lints

Author: deandreamatias

example/lib/sources/decorated_radio_checkbox.dart

@@ -156,7 +156,9 @@ class _DecoratedRadioCheckboxState extends State<DecoratedRadioCheckbox> {
 
   /// options using column of widgets for the label
   /// We can force a min width by creating a sized box so we don't need another parameter
-  List<FormBuilderFieldOption> getDemoOptionsWidgets({forceMinWidth = 0.0}) {
+  List<FormBuilderFieldOption> getDemoOptionsWidgets({
+    double forceMinWidth = 0.0,
+  }) {
     return [
       FormBuilderFieldOption(
         value: "airplane",

lib/src/fields/form_builder_switch.dart

@@ -136,7 +136,7 @@ class FormBuilderSwitch extends FormBuilderFieldDecoration<bool> {
                        field.didChange(value);
                      }
                    : null,
-               activeColor: activeColor,
+               activeThumbColor: activeColor,
                activeThumbImage: activeThumbImage,
                activeTrackColor: activeTrackColor,
                inactiveThumbColor: inactiveThumbColor,

lib/src/form_builder_field.dart

@@ -37,9 +37,6 @@ class FormBuilderField<T> extends FormField<T> {
   /// Called when the field value is changed.
   final ValueChanged<T?>? onChanged;
 
-  /// Called when the field value is reset.
-  final VoidCallback? onReset;
-
   /// {@macro flutter.widgets.Focus.focusNode}
   final FocusNode? focusNode;
 
@@ -54,10 +51,10 @@ class FormBuilderField<T> extends FormField<T> {
     super.restorationId,
     required super.builder,
     super.errorBuilder,
+    super.onReset,
     required this.name,
     this.valueTransformer,
     this.onChanged,
-    this.onReset,
     this.focusNode,
   });
 
@@ -228,7 +225,6 @@ class FormBuilderFieldState<F extends FormBuilderField<T>, T>
     if (_customErrorText != null) {
       setState(() => _customErrorText = null);
     }
-    widget.onReset?.call();
   }
 
   /// Validate field

lib/src/widgets/grouped_checkbox.dart

@@ -325,9 +325,9 @@ class GroupedCheckbox<T> extends StatelessWidget {
       ],
     );
 
-    if (this.itemDecoration != null) {
+    if (itemDecoration != null) {
       compositeItem = Container(
-        decoration: this.itemDecoration,
+        decoration: itemDecoration,
         margin: EdgeInsets.only(
           bottom: orientation == OptionsOrientation.vertical
               ? wrapSpacing