coursera: deprecating API endpoint onDemandCourseMaterials.v1

Hello, at Coursera we are in the process of deprecating the onDemandCourseMaterials.v1 endpoint. When looking for usages of this API we found it used externally here and wanted to notify the project owners that this endpoint will soon have traffic shut off. The onDemandCourseMaterials.v2 endpoint can serve as an alternative to onDemandCourseMaterial.v1