I had the exact same thing. Test failed in ./Themes/default/languages/index.english.php because it said '// Version: 2.0.7;' ... and I keep up with all updates/patches/etc.
Similar, I also keep updated, currently running 2-0.9. Got a test failed, but on mine it says,
./Themes/default/languages/index.english.php
Code: (Find) [Select]
// Version: 2.0.8;
Code: (Replace) [Select]
// Version: 2.0.10;
This is with the patch from the upgrades page. Not asking for support, just saying.

I'm guessing as my other site upgraded fine, but that had a fresh set of files uploaded a week or two back. But the site getting the test failed has been upgraded using the patches for the last few versions, it has something to do with this.