The captchas in production are registered conditional, in tests the
class needs to be added to the autoloader.
Moved this register up to setUp to detect the existing @covers correctly
by the new testValidCovers from
I1d564bcae2bfbedb004c440b90db6341148ed4ba
Change-Id: I79f225126d7bbbfd436ab165bb98a0ed9517b8bc