Refresh items which may have had their dangling state changed.

While it's tempting to look at the changed flag that TestDanglingEnds
returns, it's insuficient as the connectivity algorithm might have
already updated it (and ignored the changed flag).

Fixes: lp:1835107
* https://bugs.launchpad.net/kicad/+bug/1835107

eeschema/sch_edit_frame.cpp

@@ -1028,6 +1028,9 @@ void SCH_EDIT_FRAME::AddItemToScreenAndUndoList( SCH_ITEM* aItem, bool aUndoAppe
         }
 
         TestDanglingEnds();
+
+        for( SCH_ITEM* item : aItem->ConnectedItems() )
+            RefreshItem( item );
     }
 
     GetCanvas()->Refresh();