upgraded libffi to 3.4.8

Author: nicolaslg

.github/workflows/env_macos.sh

@@ -13,4 +13,4 @@ spack repo add ./spack_recipes/meshing_supersede
 
 spack external find cmake
 spack compiler find
-spack install --only dependencies gmds+python~blocking+cgns ^cgns~mpi ^hdf5~mpi
+spack install --only dependencies gmds+python~blocking+cgns ^cgns~mpi ^hdf5~mpi ^libffi@3.4.8