### 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)

if (co && co->can_process()) {
						new_collider = result.collider_id;
						if (!capture_object) {
							last_object = co;
							last_id = result.collider_id;
							if (co->get_capture_input_on_drag() && mb.is_valid() && mb->get_button_index() == MouseButton::LEFT && mb->is_pressed()) {
								physics_object_capture = last_id;
							}
						}
					}
					if (is_mouse && new_collider != physics_object_over) {
						if (physics_object_over.is_valid()) {
							CollisionObject3D *previous_co = Object::cast_to<CollisionObject3D>(ObjectDB::get_instance(physics_object_over));
							if (previous_co) {
								previous_co->_mouse_exit();
							}
						}
						if (new_collider.is_valid()) {
							DEV_ASSERT(co);
							co->_mouse_enter();
						}
						physics_object_over = new_collider;
					}
					if (capture_object) {
						_collision_object_3d_input_event(capture_object, camera_3d, ev, result.position, result.normal, result.shape);
					} else if (new_collider.is_valid()) {
						_collision_object_3d_input_event(co, camera_3d, ev, result.position, result.normal, result.shape);
					}
				}
				last_pos = pos;