fix: do not advertise incremental sync mode for streams without cursor field

Co-Authored-By: AJ Steers <aj@airbyte.io>

Author: devin-ai-integration[bot]

airbyte_cdk/sources/declarative/parsers/model_to_component_factory.py

@@ -2112,9 +2112,7 @@ def create_default_stream(
             primary_key=get_primary_key_from_stream(primary_key),
             cursor_field=concurrent_cursor.cursor_field
             if hasattr(concurrent_cursor, "cursor_field")
-            else CursorField(
-                cursor_field_key=""
-            ),  # FIXME we should have the cursor field has part of the interface of cursor,
+            else None,
             logger=logging.getLogger(f"airbyte.{stream_name}"),
             cursor=concurrent_cursor,
             supports_file_transfer=hasattr(model, "file_uploader") and bool(model.file_uploader),