Fixed test case (new text broke it)

What would happen if you run the tests using e.g. `cs_CZ.UTF-8` locale with available translations for these strings? I guess it would fail...

Comparing translation result is quite fragile. You should either
- really ensure that the test is running in English (or `POSIX` or `C` locale)
- or just set the expectation to simple `be_a(String)`
- or compare it to `_("Graphical mode")`