Meltano

Anyone familiar with `target-redshift` from Pipelinewise (<https://github.com/transferwise/pipelinewise-target-redshift/tree/master|link>)? I seem to be encountering a bug and not sure if others have also run into it. In the function `persist_lines` we set `state = None` (<https://github.com/transferwise/pipelinewise-target-redshift/blob/master/target_redshift/__init__.py#L116|link>), but then <https://github.com/transferwise/pipelinewise-target-redshift/blob/master/target_redshift/__init__.py#L193|pass it without modification> to `flush_streams`. `flush_streams` then thinks it's a dictionary and <https://github.com/transferwise/pipelinewise-target-redshift/blob/master/target_redshift/__init__.py#L332|calls get on it>, which is an error.

I have been using this target for a while and somehow only just now hit this error. I suppose we could set it to an empty dictionary instead but I'm not sure if this is the right fix.