`print.ped()` should return the pedigree (not the data frame) invisibly

[magnusdv]

x = pedtools::nuclearPed() |> print()
#>  id fid mid sex
#>   1   *   *   1
#>   2   *   *   2
#>   3   1   2   1

class(x)
#> [1] "data.frame"

^{Created on 2023-03-24 with reprex v2.0.2}