[Python-apps-team] Bug#844081: Reproducer

[Christian Geier]

Hi Filip,
could you perhaps try to change all those sleep()s to `os.sync()`? For
me it seems to fix the issue.

See [0] for a patch.

If this doesn fix the issue, we obviously need to move the sync call out
of the tests and into the db update.

Best regards,
Christian

[0] https://github.com/pimutils/khal/commit/0b636f7633e86b9e136b06e9965cd3af0e3918f2