Removed no-shuffle tag and fixed leak in debug_test.dart (#88268)

Co-authored-by: Alexander Dahlberg <alexander.dahlberg@sigma.se>

The TapGestureRecognizer in the test named 'TapGestureRecognizer _sentTapDown toString' was not disposed, which was breaking a couple of other tests.
This worked fine when not shuffling the tests as the test was executed last.

packages/flutter/test/gestures/debug_test.dart

@@ -2,12 +2,6 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-// TODO(gspencergoog): Remove this tag once this test's state leaks/test
-// dependencies have been fixed.
-// https://github.com/flutter/flutter/issues/85160
-// Fails with "flutter test --test-randomize-ordering-seed=123"
-@Tags(<String>['no-shuffle'])
-
 import 'package:flutter/foundation.dart';
 import 'package:flutter/gestures.dart';
 import 'package:flutter_test/flutter_test.dart';
@@ -160,5 +154,7 @@ void main() {
     tap.addPointer(event);
     tap.didExceedDeadline();
     expect(tap.toString(), equalsIgnoringHashCodes('TapGestureRecognizer#00000(state: possible, button: 1, sent tap down)'));
+    GestureBinding.instance!.gestureArena.close(1);
+    tap.dispose();
   });
 }