Configuration doesn't work with duration_field 2.x release

It would be nice to get this committed. I tested the patch and the error disappears. All functionality seems to work like expected.

@jukka792 & Dries Arnolds thanks for review. looks good to me.

Note that the MR already solves this. The patch in #11 works but I think it is better to rely on the methods provided in the Duration Field module.

See:

$duration = $this->durationService->getDurationStringFromDateInterval($duration);

Automatically closed - issue fixed for 2 weeks with no activity.