fix: use WFS POST for historical land use

backend/tests/test_sprint187_temporal_map_foundation.py

@@ -245,6 +245,7 @@ def test_temporal_frontend_and_official_operator_contracts_exist() -> None:
     assert "/temporal/compare" in temporal_api
     assert "Statbel" in population and "area_weighted_sum" in population
     assert "HistLandgebruik" in landuse and "intersection_area" in landuse
+    assert "<wfs:GetFeature" in landuse and "session.post(" in landuse
     assert "provision_mol_population_history.py" in dockerfile
     assert "provision_mol_historical_landuse.py" in dockerfile
     assert "fake" not in population.lower()