feat: add support for --comment CLI param, to set versioning comment

only relevant if Wutta-Continuum is enabled

tests/cli/test_base.py

@@ -53,11 +53,19 @@ class TestImportCommandHandler(DataTestCase):
                 self.__dict__.update(kw)
 
         with patch.object(handler, "import_handler") as import_handler:
-            parent = Mock(params={"runas_username": "fred"})
+            parent = Mock(
+                params={
+                    "runas_username": "fred",
+                    "comment": "hello world",
+                }
+            )
             # TODO: why can't we just use Mock here? the parent attr is problematic
             ctx = Object(params={"models": []}, parent=parent)
             handler.run(ctx)
-            import_handler.process_data.assert_called_once_with(runas_username="fred")
+            import_handler.process_data.assert_called_once_with(
+                runas_username="fred",
+                transaction_comment="hello world",
+            )
 
     def test_list_models(self):
         handler = self.make_handler(