[IMP] mass_editing: Work with integration tests

Execute tests at the end after the module loading for not failing with a
required field not filled by default defined in other modules.

mass_editing/tests/test_mass_editing.py

@@ -9,6 +9,8 @@ from ..hooks import uninstall_hook
 
 
 class TestMassEditing(common.TransactionCase):
+    at_install = False
+    post_install = True
 
     def setUp(self):
         super(TestMassEditing, self).setUp()