javaunohelper: use java.util.logging in tests

Change-Id: Icdc61dc88a11afae5257bcddda32adb691cb5883
Reviewed-on: https://gerrit.libreoffice.org/11564
Reviewed-by: Chris Sherlock <chris.sherlock79@gmail.com>
Tested-by: Chris Sherlock <chris.sherlock79@gmail.com>