[Task]: Make `Maintenance respiration` differentiable and efficient

The module [`Maintenance respiration`](https://github.com/ajwdewit/pcse/blob/master/pcse/crop/respiration.py) has class `WOFOST_Maintenance_Respiration` that should be changed. See explanations and requirements in https://github.com/WUR-AI/diffWOFOST/issues/39.