Add gromacs 2024 ~mpi

Without MPI for two reasons:

• for situations that don't need MPI, threadMPI is often faster
• to prepare for eventually adding with +plumed and +cufftmp. Even though the +plumed appears in the name, it's less confusion (since there will only be one -mpi* module.

assigned to @ddossant

requested review from @richart

Concerning the review, I think you are back to work today. If not, ignore this until tomorrow :-)

I suggest ~~mpi in case some other dependencies have the mpi variants

added 1 commit

• c49fcba7 - Force ~mpi for all gromacs dependencies

Compare with previous version

resolved all threads

mentioned in commit 38194854

merged