I'm a bit worried that some of our random test failures are related to
trying to reuse the same temp file in different tests.

Change-Id: I0ca4ace088a96530e6a62d01f979fefe63822b22
Reviewed-on: https://gerrit.libreoffice.org/21090Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Markus Mohrhard <markus.mohrhard@googlemail.com>