AthContainers: c++20 fix

std::is_pod is deprecated.

Control/AthContainers/AthContainers/tools/AuxTypeVector.icc

 /*
-  Copyright (C) 2002-2017 CERN for the benefit of the ATLAS collaboration
+  Copyright (C) 2002-2021 CERN for the benefit of the ATLAS collaboration
 */
-
-// $Id$
 /**
  * @file AthContainers/tools/AuxTypeVector.icc
  * @author scott snyder <snyder@bnl.gov>
@@ -421,7 +419,8 @@ bool AuxTypeVectorHolder<T, CONT>::insertMove (size_t pos, void* beg, void* end)
   insertMove1 (m_vecPtr->begin() + pos*SCALE,
                reinterpret_cast<element_type*> (beg),
                reinterpret_cast<element_type*> (end),
-               typename std::is_pod<element_type>::type());
+               typename std::conjunction<std::is_standard_layout<element_type>,
+                                         std::is_trivial<element_type> >::type());
   return m_vecPtr->data() == orig;
 }