### 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)

mm.instantiate();
		mm->set_device(InputEvent::DEVICE_ID_INTERNAL);
		mm->set_position(get_mouse_position());
		mm->set_global_position(mm->get_position());
		mm->set_alt_pressed(Input::get_singleton()->is_key_pressed(Key::ALT));
		mm->set_shift_pressed(Input::get_singleton()->is_key_pressed(Key::SHIFT));
		mm->set_ctrl_pressed(Input::get_singleton()->is_key_pressed(Key::CTRL));
		mm->set_meta_pressed(Input::get_singleton()->is_key_pressed(Key::META));
		mm->set_button_mask(Input::get_singleton()->get_mouse_button_mask());
		physics_picking_events.push_back(mm);
	}
	while (physics_picking_events.size()) {
		Ref<InputEvent> ev = physics_picking_events.front()->get();
		physics_picking_events.pop_front();
		Vector2 pos;
		bool is_mouse = false;
		Ref<InputEventMouseMotion> mm = ev;
		if (mm.is_valid()) {
			pos = mm->get_position();
			is_mouse = true;
		}
		Ref<InputEventMouseButton> mb = ev;
		if (mb.is_valid()) {
			pos = mb->get_position();
			is_mouse = true;
		}
		Ref<InputEventScreenDrag> sd = ev;
		if (sd.is_valid()) {
			pos = sd->get_position();
		}