Handle unprocessed requests in `batch_add_requests`

[Pijukatel]

in _request_queue_client.py (async and sync client) there is a batch_add_requests method. This method is calling Apify API which can return some unprocessed requests in rare cases. This can happen for example due to rate limiting when there is high load. Currently it seems that those unprocessed requests are not handled in any way and will be just ignored.

Maybe the method should at least retry to add unprocessed requests in some final batch? Maybe with some backoff?

(Some context apify/crawlee-python#1155 (comment))

[B4nan]

IIRC we deal with this in crawlee, at least in the JS version.

[Pijukatel]

IIRC we deal with this in crawlee, at least in the JS version.

I do not think it is done in Python version. There we assume it just works and we only print the response. This response can contain info about unprocessed requests, but we do not handle that there.

@janbuchar I might have missed some handling on some other level, so please correct me if I am wrong.