amber package: add ambertools21 for @20 (#28064)
amber package: add ambertools21 for @20 (#28064)

* [amber] added 3 more patches for amber20
* [amber] updated dependencies for @20 (cuda, parallel-netcdf)
LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack,LLNL/spack