Jenkins reproducibly_build jobs lack ISOs and their checksums

See e.g. Jenkins’ otherwise successful attempt for Tails 3.9.1: https://jenkins.tails.boum.org/job/reproducibly_build_Tails_ISO_stable/456/

12:53:04 + sudo TMPDIR=/var/lib/jenkins/workspace/reproducibly_build_Tails_ISO_stable diffoscope --text /var/lib/jenkins/workspace/reproducibly_build_Tails_ISO_stable/build-artifacts/diffoscope.txt --html /var/lib/jenkins/workspace/reproducibly_build_Tails_ISO_stable/build-artifacts/diffoscope.html --max-report-size 262144000 --max-diff-block-lines 10000 --max-diff-input-lines 10000000 /var/lib/jenkins/workspace/reproducibly_build_Tails_ISO_stable/build-artifacts/1/tails-amd64-3.9.1.iso /var/lib/jenkins/workspace/reproducibly_build_Tails_ISO_stable/build-artifacts/2/tails-amd64-3.9.1.iso

Here we see that the images are 1/*.iso and 2/*.iso.

12:53:09 + ls -d tails-* 1/tails-build-env.list 2/tails-amd64-3.9.1.iso.apt-sources 2/tails-amd64-3.9.1.iso.build-manifest 2/tails-amd64-3.9.1.iso.buildlog 2/tails-amd64-3.9.1.iso.packages diffoscope.*
12:53:09 ls: cannot access 'tails-*': No such file or directory
12:53:09 ls: cannot access 'diffoscope.*': No such file or directory
12:53:09 + sha512sum 1/tails-build-env.list
12:53:09 + sha512sum 2/tails-amd64-3.9.1.iso.apt-sources
12:53:09 + sha512sum 2/tails-amd64-3.9.1.iso.buildlog
12:53:09 + sha512sum 2/tails-amd64-3.9.1.iso.build-manifest
12:53:09 + sha512sum 2/tails-amd64-3.9.1.iso.packages
12:53:09 + gpg --batch --detach-sign --armor tails-build-artifacts.shasum

Here it the ls -d tails-* part looks wrong, it should be something like {1,2}/tails-*.iso.

Original created by @anonym on 16026 (Redmine)