tests,libtracker-fts: use a more generic test string for chinese parser tests

Instead of a made up string, which doesn't have any true meaning, and which
makes libicu and libunistring differ on the number of words found, use a simpler
sentence...

https://bugzilla.gnome.org/show_bug.cgi?id=699412
tests,libtracker-fts: always run full unicode tests

We no longer have the glib/pango parser, so just enable all unicode tests.