message: Add copyright to Github files
diff: +# Copyright (c) 2010-2021, Lawrence Livermore National Security, LLC. Produced
  +# at the Lawrence Livermore National Laboratory. All Rights reserved. See files
  +# LICENSE and NOTICE for details. LLNL-CODE-806117.
  +#
  +# This file is part of the MFEM library. For more information and source code
  +# availability visit https://mfem.org.
  +#
  +# MFEM is free software; you can redistribute it and/or modify it under the
  +# terms of the BSD-3 license. We welcome feedback and contributions, see file
  +# CONTRIBUTING.md for details.
  +
  name: repo-check
  on:
  