[python] Make bindings work with dune 2.9
This is a second attempt at !2912 (closed) to make Python work with dune 2.8 and dune 2.9. The two versions feature incompatible ways of setting up the Python bindings.
Edited by Timo Koch
This is a second attempt at !2912 (closed) to make Python work with dune 2.8 and dune 2.9. The two versions feature incompatible ways of setting up the Python bindings.