Cvpcb: fix crash when trying to associate a footprint to a symbol.

(the undo/redo list is specific to Cvpcb and does not use a
UNDO_REDO_CONTAINER container).
Fixes #14948
https://gitlab.com/kicad/code/kicad/-/issues/14948

cvpcb/cvpcb_mainframe.h

@@ -2,7 +2,7 @@
  * This program source code file is part of KiCad, a free EDA CAD application.
  *
  * Copyright (C) 2018 Jean-Pierre Charras, jp.charras at wanadoo.fr
- * Copyright (C) 1992-2021 KiCad Developers, see AUTHORS.txt for contributors.
+ * Copyright (C) 1992-2023 KiCad Developers, see AUTHORS.txt for contributors.
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
@@ -186,6 +186,18 @@ public:
         return m_redoList.size();
     }
 
+    // Cvpcb does not handle a undo/redo description (it does not use a UNDO_REDO_CONTAINER,
+    // but a CVPCB_UNDO_REDO_LIST to store the undo/redo commands)
+    wxString GetUndoActionDescription() const override
+    {
+        return wxEmptyString;
+    }
+
+    wxString GetRedoActionDescription() const override
+    {
+        return wxEmptyString;
+    }
+
     /**
      * Associate a footprint with a specific component in the list.
      *