[BW] Use data from Geoportal

[k-nut]

The ministry of education of Baden-Württemberg seems to provide an INSPIRE WFS service for school locations. The output is a bit more convoluted than we are used to from other states but I think it would still be worth it to switch (especially since we would get reliable geo-locations): Start URL could be https://gis.kultus-bw.de/geoserver/us-govserv/ows?service=WFS&request=GetFeature&typeNames=us-govserv%3AGovernmentalService&outputFormat=application%2Fjson

GetCapabilities for the endpoint is: https://gis.kultus-bw.de/geoserver/us-govserv/ows?service=WFS&request=GetCapabilities