journalctl randomly fails to read the main journal file

If journal file rotation occurs during journalctl invocation, we hit something like the following, and we cannot read the newly archived journal file and/or the new main journal file.

Journal file /var/log/journal/748efedc39f24d60dee8bee36937d73f/system.journal is truncated, ignoring file.

This should be caused by the optimization done by bd1af1d5fb1db9a77e8738ec108bf60ff0cb15f1.

To workaround the issue, nowadays we insert bunch of journalctl --sync and/or --rotate in our integration tests, but that should be gracefully handled by sd-journal side.