Disable leak tracking for selection text area (#147273)

Author: ValentinVignal

packages/flutter/test/material/selection_area_test.dart

@@ -9,7 +9,6 @@ import 'package:flutter/material.dart';
 import 'package:flutter/rendering.dart';
 import 'package:flutter/services.dart';
 import 'package:flutter_test/flutter_test.dart';
-import 'package:leak_tracker_flutter_testing/leak_tracker_flutter_testing.dart';
 
 import '../widgets/process_text_utils.dart';
 
@@ -289,10 +288,7 @@ void main() {
     expect(content!.plainText, 'How');
   });
 
-  testWidgets('stopping drag of end handle will show the toolbar',
-    // TODO(polina-c): remove when fixed https://github.com/flutter/flutter/issues/145600 [leak-tracking-opt-in]
-    experimentalLeakTesting: LeakTesting.settings.withTracked(classes: const <String>['CurvedAnimation']),
-    (WidgetTester tester) async {
+  testWidgets('stopping drag of end handle will show the toolbar', (WidgetTester tester) async {
     final FocusNode focusNode = FocusNode();
     addTearDown(focusNode.dispose);