Don't leave deleted items in group

We filter out ref/value text in copies so we need to remove them from
the copied group (if any) as well

Fixes https://gitlab.com/kicad/code/kicad/-/issues/15930

(cherry picked from commit fb387a2c09)

pcbnew/kicad_clipboard.cpp

@@ -170,6 +170,7 @@ void CLIPBOARD_IO::SaveSelection( const PCB_SELECTION& aSelected, bool isFootpri
             // Now delete items, duplicated but not added:
             for( BOARD_ITEM* skp_item : skipped_items )
             {
+                static_cast<PCB_GROUP*>( clone )->RemoveItem( skp_item );
                 skp_item->SetParentGroup( nullptr );
                 delete skp_item;
             }