[fix] base_import_async: drop test requirements and remove comment

Author: tishmen

base_import_async/wizard/base_import_import.py

@@ -80,7 +80,6 @@ def _link_attachment_to_job(self, delayed_job, attachment):
         attachment.write({"res_model": "queue.job", "res_id": queue_job.id})
 
     def _create_csv_attachment(self, fields, data, options, file_name):
-        # Odoo 19: @api.returns decorator removed; just return the recordset.
         # write csv
         f = StringIO()
         writer = csv.writer(