cleaned up tests related to trace logging non-ascii return values. now they may pass also with ipy.
cleaned up tests related to trace logging non-ascii return values. now they may pass also with ipy.

userzimmermann/robotframework-python3,userzimmermann/robotframework-python3,userzimmermann/robotframework-python3,userzimmermann/robotframework-python3,userzimmermann/robotframework-python3