bemade_fsm: Marking visit task done doesn't create SO line.

Added a test to confirm that marking the task associated to a visit
does not create an additional sale order line like it did before.

Fixes Dur-Pro/bemade-addons#93

bemade_fsm/tests/test_fsm_visit.py

@@ -114,3 +114,11 @@ class FSMVisitTest(BemadeFSMBaseTest):
         self.assertEqual(sol1.qty_to_deliver, 0)
         self.assertEqual(sol2.qty_to_deliver, 0)
         self.assertTrue(visit.is_completed)
+
+    def test_marking_visit_done_does_not_create_sale_order_line(self):
+        so, visit, sol1, sol2 = self._generate_so_with_one_visit_two_lines()
+        so.action_confirm()
+
+        visit.task_id.action_fsm_validate()
+
+        self.assertEqual(len(so.order_line), 3)