Add a MemoryStream version of CreateReportAndDownloadFileAsync

[shoecake]

In the report service, can we have a CreateReportAndDownloadStreamAsync function. This would work in the same way as CreateReportAndDownloadFileAsync but would not save the report to a file but would return the report as a MemoryStream.

That way if the code needs to process the report as soon as it is available, it would save having to write to the filesystem only to then immediately read it back.