Make sure all test are working on {pipapi}

[randrescastaneda]

HI @shahronak47 ,

I checked out a new branch from "dev" in the {pipapi} package and, when testing that my modifications were working fine, I found out that some of the files used to test other functions are not available in the branch and there's no evident way of how to get them. For isntance, the following file does no exist.

fst::read_fst("../testdata/app_data/20210401/estimations/interpolated_means.fst")

Could you please make sure that all the files are easily generated from the package and are available in the "dev" branch?

Thanks.