Enclosure has problems with rivers

[ale-v]

Although I specified streets and land as spatial constraints for generating the enclosures, the momepy.enclosures wrongly creates enclosures in rivers. See the yellow areas in the pic.

[martinfleis]

I think that we'll have to add some spatial filter before we return polygons. The operation itself is just polygonize, that's why these areas are returned. I just don't want to do it every time because it can be expensive. Will have to figure out some smart solution.