Parallelize async insight report jobs

[pnadolny13]

The tap gets reports using the async job workflow but we only kick off one job right now and wait for it to complete. We can kick off many of them at once and then poll for completion, even keeping them in order so the stream is sorted if we wanted. Since several other jobs will be processing while we poll for the first one, I'd expect all of them to be ready to extract once the first one is done. This would allow us to increase throughput significantly.