How to get the asset folder

am currently writing a Gradle plugin for Android, and one of the tasks needs to analyze the assets to be put in the app. Using the standard directory to the assets src/main/assets works for the task, however according to this question, it is possible to set different custom sources for assets.

How can one get the correct path to the configured assets folder in an Gradle plugin?

I have already spent a lot of time to read documentation and other questions to figure out the correct way to do so, but have not found a clear answer so far, especially since a good amount of them is out of date.

Most of them (e.g. How to access assets directory in a Gradle plugin) reference the SourceSets property of the Project object, which is no longer part of the API.