Before this change, 2FA with OTP was enabled before the user was able to
submit a code to validate the setup. Thus, this could lead to a
situation where the user is locked out of her account if there was an
issue setting up her application.
Now we rely on a new boolean property that is set to true only after the
user submits a valid code during the setup phase.
Fixes#4867
Signed-off-by: Kevin Decherf <kevin@kdecherf.com>