Different columns returned by `deepdep()` when no dependencies

[ErdaradunGaztea]

When you call:

deepdep::deepdep("versionsort")

and

deepdep::deepdep("stringi")

the returned data frames have different columns:

The latter are correct, probably the effect of deleting base R dependencies (stringi have a few, versionsort has none).

[DominikRafacz]

@ErdaradunGaztea this problem turns out more serious that we initially thought, because I discovered that those plots cannot be plotted in some specific circumstances (probably related to changes to {igraph}). A fix of that sub-issue will be included in quickfix version of 0.4.2