### 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
Point2i button_ofs = Point2i(ofs + item_width_with_buttons - button_size.width, p_pos.y) - theme_cache.offset + p_draw_ofs;
				if (cache.click_type == Cache::CLICK_BUTTON && cache.click_item == p_item && cache.click_column == i && cache.click_index == j && !p_item->cells[i].buttons[j].disabled) {
					
					Point2 od = button_ofs;
					if (rtl) {
						od.x = get_size().width - od.x - button_size.x;
					}
					theme_cache.button_pressed->draw(get_canvas_item(), Rect2(od.x, od.y, button_size.width, MAX(button_size.height, label_h)));
				}
				button_ofs.y += (label_h - button_size.height) / 2;
				button_ofs += theme_cache.button_pressed->get_offset();
				if (rtl) {
					button_ofs.x = get_size().width - button_ofs.x - button_texture->get_width();
				}
				button_texture->draw(ci, button_ofs, p_item->cells[i].buttons[j].disabled ? Color(1, 1, 1, 0.5) : p_item->cells[i].buttons[j].color);
				item_width_with_buttons -= button_size.width + theme_cache.button_margin;
			}
			if (i == 0) {
				ofs = get_column_width(0);
			} else {
				ofs += item_width + buttons_width;
			}
			if (select_mode == SELECT_MULTI && selected_item == p_item && selected_col == i) {
				if (is_layout_rtl()) {
					cell_rect.position.x = get_size().width - cell_rect.position.x - cell_rect.size.x;
				}
				if (has_focus()) {
					theme_cache.cursor->draw(ci, cell_rect);
				} else {
					theme_cache.cursor_unfocus->draw(ci, cell_rect);