Replace UnexpectedError with UnexpectedApiError in filter
Replace `UnexpectedError` with `UnexpectedApiError` in filter endpoint, so that it is aligned with the other endpoints. This misalignment was introduced after the simultaneous merge of:
- #1475 
- #1418
Replace UnexpectedError with UnexpectedApiError in filter: Replace `UnexpectedError` with `UnexpectedApiError` in filter endpoint, so that it is aligned with the other endpoints. This misalignment was introduced after the simultaneous merge of:
- #1475 
- #1418