Provide default for feedback_file_names

Author: david-yz-liu

markus_autotesting_core/types/types.py

@@ -99,7 +99,7 @@ class BaseTestData(
     timeout: Annotated[int, Meta(title="Timeout")] = 30
     """The timeout in seconds for this test group."""
 
-    feedback_file_names: Annotated[list[str], Meta(title="Feedback files")]
+    feedback_file_names: Annotated[list[str], Meta(title="Feedback files")] = []
     """A list of file paths generated by executing this test group."""
 
     extra_info: Annotated[