### 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;
	ERR_FAIL_NULL(p_viewport);
	ERR_FAIL_NULL(p_control);
	if (gui.mouse_focus) {
		p_viewport->gui.mouse_focus = p_control;
		p_viewport->gui.mouse_focus_mask = gui.mouse_focus_mask;
		p_viewport->gui.key_focus = p_control;
		p_viewport->gui.forced_mouse_focus = true;
		gui.mouse_focus = nullptr;
		gui.forced_mouse_focus = false;
		gui.mouse_focus_mask.clear();
	}
}
void Viewport::set_sdf_oversize(SDFOversize p_sdf_oversize) {
	ERR_MAIN_THREAD_GUARD;
	ERR_FAIL_INDEX(p_sdf_oversize, SDF_OVERSIZE_MAX);
	sdf_oversize = p_sdf_oversize;
	RS::get_singleton()->viewport_set_sdf_oversize_and_scale(viewport, RS::ViewportSDFOversize(sdf_oversize), RS::ViewportSDFScale(sdf_scale));
}
Viewport::SDFOversize Viewport::get_sdf_oversize() const {
	ERR_READ_THREAD_GUARD_V(SDF_OVERSIZE_100_PERCENT);
	return sdf_oversize;
}
void Viewport::set_sdf_scale(SDFScale p_sdf_scale) {
	ERR_MAIN_THREAD_GUARD;
	ERR_FAIL_INDEX(p_sdf_scale, SDF_SCALE_MAX);
	sdf_scale = p_sdf_scale;
	RS::get_singleton()->viewport_set_sdf_oversize_and_scale(viewport, RS::ViewportSDFOversize(sdf_oversize), RS::ViewportSDFScale(sdf_scale));
}
Viewport::SDFScale Viewport::get_sdf_scale() const {