### 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
TreeItem *from = p_at;
	TreeItem *loop = nullptr; 
	while (p_at) {
		for (int i = 0; i < columns.size(); i++) {
			if (p_at->get_text(i).findn(p_find) == 0 && (!p_selectable || p_at->is_selectable(i))) {
				if (r_col) {
					*r_col = i;
				}
				return p_at;
			}
		}
		if (p_backwards) {
			p_at = p_at->get_prev_visible(true);
		} else {
			p_at = p_at->get_next_visible(true);
		}
		if ((p_at) == from) {
			break;
		}
		if (!loop) {
			loop = p_at;
		} else if (loop == p_at) {
			break;
		}
	}
	return nullptr;
}
TreeItem *Tree::search_item_text(const String &p_find, int *r_col, bool p_selectable) {