Fix failing mpich build tests (#19259)
Fix failing mpich build tests (#19259)

By default Spack uses the latest (highest version) GCC 
compiler available, which might change across updates
of the Github CI environment.

Since a C compiler is always installed and `mpich~fortran`
will result in faster build times, avoid building the FORTRAN
interface as part of the test.
iulian787/spack,LLNL/spack,LLNL/spack,iulian787/spack,LLNL/spack,iulian787/spack,iulian787/spack,LLNL/spack,iulian787/spack,LLNL/spack