tests: Deal with Python output differences.

tests: Deal with Python output differences.

This test checks the output based on Python's string representation of
an array of two unicode strings.  These strings have a "u" prefix in
Python 2, but not Python 3.  In Python 3, all strings are unicode.

Use sed on the output to strip the "u" from Python 2 output when
checking for the expected result.

Signed-off-by: Russell Bryant <russell@ovn.org>
Acked-by: Ben Pfaff <blp@ovn.org>