Before this commit, we didn't print *_example.log files and
test_suite.log.
Printing is now handled in a separate action, which avoids code
duplication and makes the ci.yml file more readable. This changes the
folding/grouping of the log output in the GitHub Actions CI, but I
think the new variant is as good as the old one.
Furthermore, the condition for printing the logs is changed from
"always()" to "!cancelled()". This ensures that logs will still be
printed if previous steps such as the CI script failed, but that they
won't be printed if the entire run is cancelled (e.g., by clicking a
button in the UI or through a force-push to the PR). This is in line
with a recommendation in the GHA docs:
https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/evaluate-expressions-in-workflows-and-actions#always
