scripts: Don't capture output in prepare-release-pr.py (#8805)
scripts: Don't capture output in prepare-release-pr.py (#8805)

We don't need to access the output in the script, and if we capture it,
we don't get any output on CI, so no way to see why a release failed.
markshao/pytest,RonnyPfannschmidt/pytest,pytest-dev/pytest,Akasurde/pytest