### 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_MAIN_THREAD_GUARD;
	if (world_2d == p_world_2d) {
		return;
	}
	if (is_inside_tree()) {
		RenderingServer::get_singleton()->viewport_remove_canvas(viewport, current_canvas);
	}
	if (world_2d.is_valid()) {
		world_2d->remove_viewport(this);
	}
	if (p_world_2d.is_valid()) {
		bool do_propagate = world_2d.is_valid() && is_inside_tree();
		world_2d = p_world_2d;
		if (do_propagate) {
			_propagate_world_2d_changed(this);
		}
	} else {
		WARN_PRINT("Invalid world_2d");
		world_2d = Ref<World2D>(memnew(World2D));
	}
	world_2d->register_viewport(this);
	_update_audio_listener_2d();
	if (is_inside_tree()) {
		current_canvas = find_world_2d()->get_canvas();
		RenderingServer::get_singleton()->viewport_attach_canvas(viewport, current_canvas);
	}
}
Ref<World2D> Viewport::find_world_2d() const {