### Godot version

v4.1.stable.official [970459615]

### System information

Godot v4.1.stable - Windows 10.0.22621 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1660 Ti (NVIDIA; 31.0.15.3598) - AMD Ryzen 7 3700X 8-Core Processor (16 Threads)

### Issue description

is_input_handled() is returning True, even though set_input_as_handled() has not been called.

Example:
`func _input_event(viewport, event, shape_idx):
	print(viewport.is_input_handled())`

Returns 'True', should return 'False'

### Steps to reproduce

1. Create a new project and add a Node2D as the root
2. Add a child Area2D node containing a CollisionShape2D and a Sprite2D
3. Either create the _input_event(viewport, event, shape_idx) or connect _on_input_event(viewport, event, shape_idx)
4. Print viewport.is_input_handled()
5. True is printed.

### Minimal reproduction project

[input_test.zip](https://github.com/godotengine/godot/files/12063748/input_test.zip)

ERR_READ_THREAD_GUARD_V(nullptr);
	ERR_FAIL_COND_V(!is_inside_tree(), nullptr);
	Viewport *v = const_cast<Viewport *>(this);
	Window *w = Object::cast_to<Window>(v);
	while (!w) {
		v = v->get_parent_viewport();
		w = Object::cast_to<Window>(v);
	}
	return w;
}
void Viewport::_gui_remove_focus_for_window(Node *p_window) {