Fix setting the correct stream for cufft

Description

This is needed in case one has more than one batch per core as the stream is reset for each batch.

Checklist

• I have checked that my code follows the Octopus coding standards
• I have added tests for all the new features added in this request.

changed milestone to %12.0

added Bugfix label

assigned to @sohlmann

requested review from @nicolastd

approved this merge request

enabled an automatic merge when the pipeline for 836db154 succeeds

mentioned in commit 9e5eee56

merged