### 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
ERR_FAIL_INDEX_V(p_column, cells.size(), false);
	return cells[p_column].custom_button;
}
void TreeItem::set_text_alignment(int p_column, HorizontalAlignment p_alignment) {
	ERR_FAIL_INDEX(p_column, cells.size());
	if (cells[p_column].text_alignment == p_alignment) {
		return;
	}
	cells.write[p_column].text_alignment = p_alignment;
	cells.write[p_column].cached_minimum_size_dirty = true;
	_changed_notify(p_column);
}
HorizontalAlignment TreeItem::get_text_alignment(int p_column) const {
	ERR_FAIL_INDEX_V(p_column, cells.size(), HORIZONTAL_ALIGNMENT_LEFT);
	return cells[p_column].text_alignment;
}
void TreeItem::set_expand_right(int p_column, bool p_enable) {
	ERR_FAIL_INDEX(p_column, cells.size());
	if (cells[p_column].expand_right == p_enable) {
		return;
	}
	cells.write[p_column].expand_right = p_enable;
	cells.write[p_column].cached_minimum_size_dirty = true;
	_changed_notify(p_column);
}
bool TreeItem::get_expand_right(int p_column) const {