Fix tooltip content being cut off at some display scales

When getting the minimum size for a tooltip, we get the value as a Vector2.  Window::set_size() takes a Vector2i, so this size was getting truncated.  At certain display scales, this could be enough to cut off part of the tooltip.  Updated to call Vector2::ceil() to round up before calling Window::set_size()

Fixes #91958

scene/main/viewport.cpp

@@ -1501,6 +1501,7 @@ void Viewport::_gui_show_tooltip() {
 		r.size *= win_scale;
 		vr = window->get_usable_parent_rect();
 	}
+	r.size = r.size.ceil();
 	r.size = r.size.min(panel->get_max_size());
 
 	if (r.size.x + r.position.x > vr.size.x + vr.position.x) {