Fix MapboxDirections builder to allow use empty arrays instead of nulls

[Lebedinsky]

Fix MapboxDirections.Builder#build() method to allow setting empty arrays (waypointNames, waypointIndices, approaches). Now it cause of throwing exception when we try to call build() method.

Issue link in MAS repository.

[Guardiola31337]

👀 mapbox/mapbox-java#1081 (comment) @Lebedinsky @korshaknn

[Guardiola31337]

Is this still an issue @Lebedinsky @korshaknn? Are we good to close here?

[Lebedinsky]

@Guardiola31337 As far as I know, we still didn't handle this case, so we need to address it before close this ticket.

[korshaknn]

@Guardiola31337 it was refactored from array to list

if (approaches != null) {
        if (approaches.length != coordinates.size()) {
          throw ...
        }
        ...
      }

now:

if (!approaches.isEmpty()) {
        if (approaches.size() != coordinates.size()) {
          throw ...
        }
        ...
      }

it is possible to pass empty list (or empty array with deprecated method)
the same with waypointNames, waypointIndices
we can close it

[Guardiola31337]

Thanks for confirming @korshaknn

Closing here.

cc @Lebedinsky