### 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
}
					if (drop_mode_section == 0) {
						
						RenderingServer::get_singleton()->canvas_item_add_rect(ci, Rect2(r.position.x, r.position.y, 1, r.size.y), theme_cache.drop_position_color);
						RenderingServer::get_singleton()->canvas_item_add_rect(ci, Rect2(r.position.x + r.size.x - 1, r.position.y, 1, r.size.y), theme_cache.drop_position_color);
					}
					if (drop_mode_section == 0 || (drop_mode_section == 1 && (!p_item->get_first_child() || p_item->is_collapsed()))) {
						
						RenderingServer::get_singleton()->canvas_item_add_rect(ci, Rect2(r.position.x, r.position.y + r.size.y, r.size.x, 1), theme_cache.drop_position_color);
					}
				} else if (drop_mode_over == p_item->get_parent()) {
					if (drop_mode_section == 1 && !p_item->get_prev() ) { 
						
						RenderingServer::get_singleton()->canvas_item_add_rect(ci, Rect2(r.position.x, r.position.y, r.size.x, 1), theme_cache.drop_position_color);
					}
				}
			}
			Color cell_color;
			if (p_item->cells[i].custom_color) {
				cell_color = p_item->cells[i].color;
			} else {
				cell_color = p_item->cells[i].selected ? theme_cache.font_selected_color : theme_cache.font_color;
			}
			Color font_outline_color = theme_cache.font_outline_color;
			int outline_size = theme_cache.font_outline_size;
			Color icon_col = p_item->cells[i].icon_color;
			if (p_item->cells[i].dirty) {
				const_cast<Tree *>(this)->update_item_cell(p_item, i);
			}
			if (rtl) {