Add missing file in PN_interface test

integration/test_pn_interface.py

@@ -30,6 +30,7 @@ all_files = [   "pn_interface.alc",
                 "object_operations.alc",
                 "conformance_scd.alc",
                 "library.alc",
+                "ramify.alc",
                 "metamodels.alc",
                 "constructors.alc",
                 "modelling.alc",