Parent selector: Fix dot divider horizontal spacing

Remove `right: 0` from the parent selector dot divider so it is no
longer flush against the button edge. This allows the dot to be
properly centered horizontally between the parent selector button
and the adjacent toolbar button.

Fixes #57727

Author: jorgefilipecosta

packages/block-editor/src/components/block-toolbar/style.scss

@@ -141,7 +141,6 @@
 			display: inline-flex;
 			height: 2px;
 			position: absolute;
-			right: 0;
 			top: $grid-unit-20 - $border-width;
 			width: 2px;
 		}