workspace: Remove no longer valid comment

This comment is no longer correct, we're not inserting any actors here
to adjust for the window border, but we're modifying the allocation of
the children to adjust for that border.

Since that happens in the layout manager anyway, remove the comment
here.

https://gitlab.gnome.org/GNOME/gnome-shell/-/merge_requests/1297

js/ui/workspace.js

@@ -182,10 +182,6 @@ var WindowClone = GObject.registerClass({
         this.metaWindow._delegate = this;
         this._workspace = workspace;
 
-        // The MetaShapedTexture that we clone has a size that includes
-        // the invisible border; this is inconvenient; rather than trying
-        // to compensate all over the place we insert a ClutterActor into
-        // the hierarchy that is sized to only the visible portion.
         super._init({
             reactive: true,
             can_focus: true,