Update pandas_io.py

Author: hugolytics

pandera/io/pandas_io.py

@@ -174,6 +174,7 @@ def serialize_schema(dataframe_schema):
         "add_missing_columns": dataframe_schema.add_missing_columns,
         "title": dataframe_schema.title,
         "description": dataframe_schema.description,
+        "drop_invalid_rows":dataframe_schema.drop_invalid_rows,
     }