### 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(false);
	return own_world_3d.is_valid();
}
void Viewport::_propagate_enter_world_3d(Node *p_node) {
	if (p_node != this) {
		if (!p_node->is_inside_tree()) { 
			return;
		}
		if (Object::cast_to<Node3D>(p_node) || Object::cast_to<WorldEnvironment>(p_node)) {
			p_node->notification(Node3D::NOTIFICATION_ENTER_WORLD);
		} else {
			Viewport *v = Object::cast_to<Viewport>(p_node);
			if (v) {
				if (v->world_3d.is_valid() || v->own_world_3d.is_valid()) {
					return;
				}
			}
		}
	}
	for (int i = 0; i < p_node->get_child_count(); i++) {
		_propagate_enter_world_3d(p_node->get_child(i));
	}
}
void Viewport::_propagate_exit_world_3d(Node *p_node) {