### 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 (gui.key_focus->can_process()) {
				gui.key_focus->_call_gui_input(p_event);
			}
			if (gui.key_event_accepted) {
				set_input_as_handled();
				return;
			}
		}
		Control *from = gui.key_focus ? gui.key_focus : nullptr;
		if (from && p_event->is_pressed()) {
			Control *next = nullptr;
			Ref<InputEventJoypadMotion> joypadmotion_event = p_event;
			if (joypadmotion_event.is_valid()) {
				Input *input = Input::get_singleton();
				if (p_event->is_action_pressed("ui_focus_next") && input->is_action_just_pressed("ui_focus_next")) {
					next = from->find_next_valid_focus();
				}
				if (p_event->is_action_pressed("ui_focus_prev") && input->is_action_just_pressed("ui_focus_prev")) {
					next = from->find_prev_valid_focus();
				}
				if (p_event->is_action_pressed("ui_up") && input->is_action_just_pressed("ui_up")) {
					next = from->_get_focus_neighbor(SIDE_TOP);
				}
				if (p_event->is_action_pressed("ui_left") && input->is_action_just_pressed("ui_left")) {
					next = from->_get_focus_neighbor(SIDE_LEFT);
				}
				if (p_event->is_action_pressed("ui_right") && input->is_action_just_pressed("ui_right")) {
					next = from->_get_focus_neighbor(SIDE_RIGHT);
				}
				if (p_event->is_action_pressed("ui_down") && input->is_action_just_pressed("ui_down")) {