AbstractClient: Fix the current VD being always added to the plasma interface
When setting-up the plasma window interface we need to call `setOnAllDesktops()` after the actual virtual desktops have been set. Otherwise, the current desktop would be always added to the interface (as if the user were unsetting the "onAllDesktops" flag) and the plasma interface and KWin can get un-synced, specially if there are specific window rules. BUG: 452171 FIXED-IN: 5.24.5