fix definition of gmpflf toolchain

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Fixes toolchain dependency error:

List of toolchain dependency modules and toolchain definition do not match 
(found 
['GCC/12.3.0', 'MPICH/4.2.1-GCC-12.3.0', 'FlexiBLAS/3.3.1-GCC-12.3.0', 'FFTW/3.3.10-GCC-12.3.0', 'FFTW.MPI/3.3.10-gmpich-2024.06', 'ScaLAPACK/2.2.0-gmpich-2024.06-fb'] 
vs expected 
{'MPICH', 'GCC', 'OpenBLAS', 'ScaLAPACK', 'FFTW'})