tank_design: - update factory path of aircraft geometry 2 to Pep8 standard

tank_design/src/tube_and_wing/empirical/tank_design_tu_berlin/general/tankdesigntuberlin.py

@@ -36,7 +36,7 @@ def tank_design_tu_berlin(paths_and_names, routing_dict, dict_ac_data, runtime_o
     """
     """ Extract aerodynamic surfaces values using the aircraftGeometry2 library."""
     # Create the factory
-    airfoil_data_dir = f'{paths_and_names["project_directory"]}/geometryData/airfoilData'
+    airfoil_data_dir = f'{paths_and_names["project_directory"]}/geometry_data/airfoil_data'
     aircraft_exchange_file = aixml.openDocument(paths_and_names['path_to_aircraft_exchange_file'])
     factory = geom2.factory.WingFactory(aircraft_exchange_file, airfoil_data_dir)
     # Create the surface