### Godot version

4.0 beta 10

### System information

Windows 11 Vulkan

### Issue description

Looked through the issues list, but couldn't find something like this, sorry in advance if this has already been reported.

There is a few cases (in the pictures below) where list of Actions in Input Map may not always show a scrollbar even if the actions list overflows (I imagine this could also happen for the widget that Input Map uses).

![image](https://user-images.githubusercontent.com/39958198/210003566-cf60dbaf-921f-485b-b0a9-51ffc28d0244.png)

![New Bitmap image](https://user-images.githubusercontent.com/39958198/210004079-8eb2e6a1-0cf5-4a7c-8905-a4e3cfd0ec5d.png)

![image](https://user-images.githubusercontent.com/39958198/210004165-a6b6790b-248a-4f68-b4d0-b44b25afdf4f.png)

![image](https://user-images.githubusercontent.com/39958198/210004537-aca52194-a464-48b9-b818-24782706de45.png)


### Steps to reproduce

The pictures are clearer than anything I could write here: "a picture is worth 1000 words"

### Minimal reproduction project

N/A
valtext = String::num(p_item->cells[p_col].val, Math::range_step_decimals(p_item->cells[p_col].step));
		}
	} else {
		valtext = p_item->cells[p_col].text;
	}
	if (!p_item->cells[p_col].suffix.is_empty()) {
		valtext += " " + p_item->cells[p_col].suffix;
	}
	if (p_item->cells[p_col].text_direction == Control::TEXT_DIRECTION_INHERITED) {
		p_item->cells.write[p_col].text_buf->set_direction(is_layout_rtl() ? TextServer::DIRECTION_RTL : TextServer::DIRECTION_LTR);
	} else {
		p_item->cells.write[p_col].text_buf->set_direction((TextServer::Direction)p_item->cells[p_col].text_direction);
	}
	Ref<Font> font;
	if (p_item->cells[p_col].custom_font.is_valid()) {
		font = p_item->cells[p_col].custom_font;
	} else {
		font = theme_cache.font;
	}
	int font_size;
	if (p_item->cells[p_col].custom_font_size > 0) {
		font_size = p_item->cells[p_col].custom_font_size;
	} else {
		font_size = theme_cache.font_size;
	}
	p_item->cells.write[p_col].text_buf->add_string(valtext, font, font_size, p_item->cells[p_col].language);
	TS->shaped_text_set_bidi_override(p_item->cells[p_col].text_buf->get_rid(), structured_text_parser(p_item->cells[p_col].st_parser, p_item->cells[p_col].st_args, valtext));
	p_item->cells.write[p_col].dirty = false;
}
void Tree::update_item_cache(TreeItem *p_item) {