Duración de la transición.
Depending on AnimatorTransitionInfo.durationUnit the duration can either be expressed in seconds (i.e. DurationUnit.Fixed) or in percentage (i.e. DurationUnit.Normalized). A normalized duration is based on the source state duration.
Note: a normalized duration converted in seconds can change from frame to frame, since the source state duration can change depending on varying factors, like the weights in a blendtree.