Fix: Quick Tooltip Position Can Jiggle

Quick tooltips immediately show a word or two and then shows more
detailed information after a pause. It is possible to have these two
things shows at differing positions (vertically or horizontally) and
therefore jiggle. Some padding code uses the width and height and half
of a padding amount, which can result in differing values if the first
width or height is an odd amount but the second is even, or vice versa.
This happens quite infrequently and depends on the user scale. This PR
just replaces one line that does the padding in a way that results in
consistent values.

Pull Request: https://projects.blender.org/blender/blender/pulls/148019

source/blender/editors/interface/regions/interface_region_tooltip.cc

@@ -1606,7 +1606,7 @@ static ARegion *ui_tooltip_create_with_data(bContext *C,
 #undef USE_ALIGN_Y_CENTER
 
   /* add padding */
-  BLI_rcti_resize(&rect_i, BLI_rcti_size_x(&rect_i) + pad_x, BLI_rcti_size_y(&rect_i) + pad_y);
+  BLI_rcti_pad(&rect_i, int(round(pad_x * 0.5f)), int(round(pad_y * 0.5f)));
 
   /* widget rect, in region coords */
   {