tests: don't keep bison messages in tests

tests: don't keep bison messages in tests

Bison generates the 'syntax error' messages and depends on
the Bison version. For example, the current bison uses

        lsfd: failed to parse "(": syntax error, unexpected end of file

But the old version:

        lsfd: failed to parse "(": syntax error, unexpected $end

We do not control these strings, so it's better not to save them to our tests.

Signed-off-by: Karel Zak <kzak@redhat.com>