Remove `mget(ls()) ` in `create_moma_sparsity_func`

[Banana1530]

Ok - I understand where you are going with the formals manipulation and it's quite nice: I'm still less comfortable with mget(ls()). Since there are only 10 of these and we don't have any plans to add more, is it worth it to move away from the wrapper function approach and just hand-write 10 small functions?

Originally posted by @michaelweylandt in https://github.com/michaelweylandt/MoMA/pull/48/files