### 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 (hide_root && !root->get_next_visible()) {
			return;
		}
		if (k->get_unicode() > 0) {
			_do_incr_search(String::chr(k->get_unicode()));
			accept_event();
			return;
		} else {
			if (k->get_keycode() != Key::SHIFT) {
				last_keypress = 0;
			}
		}
	}
	Ref<InputEventMouseMotion> mm = p_event;
	if (mm.is_valid()) {
		Ref<StyleBox> bg = theme_cache.panel_style;
		bool rtl = is_layout_rtl();
		Point2 pos = mm->get_position();
		if (rtl) {
			pos.x = get_size().width - pos.x;
		}
		pos -= theme_cache.panel_style->get_offset();
		Cache::ClickType old_hover = cache.hover_type;
		int old_index = cache.hover_index;
		cache.hover_type = Cache::CLICK_NONE;
		cache.hover_index = 0;
		if (show_column_titles) {
			pos.y -= _get_title_button_height();
			if (pos.y < 0) {
				pos.x += theme_cache.offset.x;