### Godot version

4.2 dev1

### System information

Windows 10.0.19045 - Vulkan (Forward+) - dedicated NVIDIA GeForce GTX 1060 (NVIDIA; 30.0.15.1403) - Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz (8 Threads)

### Issue description

Calling `Tree.propagate_check()` after an item is unchecked does not properly uncheck the parents. They are left in partially checked state.

It's easy to observe in theme editor:

https://github.com/godotengine/godot/assets/2223172/71d0479c-0a5e-48d3-957f-d90379a95c22



### Steps to reproduce

1. Edit a Theme resource
2. Go to Manage Items... menu
3. Go to Import Items tab
4. Unfold something
5. Check and uncheck a child checkbox

### Minimal reproduction project

N/A
drag_speed = 0;
					drag_from = 0;
				}
				if (!click_handled) {
					drag_speed = 0;
					drag_accum = 0;
					
					drag_from = v_scroll->get_value();
					drag_touching = DisplayServer::get_singleton()->is_touchscreen_available();
					drag_touching_deaccel = false;
					if (drag_touching) {
						set_physics_process_internal(true);
					}
					if (mb->get_button_index() == MouseButton::LEFT) {
						if (get_item_at_position(mb->get_position()) == nullptr && !mb->is_shift_pressed() && !mb->is_ctrl_pressed() && !mb->is_command_or_control_pressed()) {
							emit_signal(SNAME("nothing_selected"));
						}
					}
				}
				if (propagate_mouse_activated) {
					emit_signal(SNAME("item_activated"));
					propagate_mouse_activated = false;
				}
			} break;
			case MouseButton::WHEEL_UP: {
				if (_scroll(false, -mb->get_factor() / 8)) {
					accept_event();
				}
			} break;
			case MouseButton::WHEEL_DOWN: {