When multiple U2F devices are linked to a google account, there will
be multiple keyhandles for the challenge. Need to try all of them,
otherwise only one of the registered U2F devices will able to succeed.
Coverage increased (+2.5%) to 49.204% when pulling a934c757e534bdd36c3b913bc56a3bf402880b04 on nrw505:cope-with-accounts-having-multiple-u2f-devices-registered into e468c011068b386375b8ecb686323bf69e503633 on cevoaustralia:master.
When multiple U2F devices are linked to a google account, there will be multiple keyhandles for the challenge. Need to try all of them, otherwise only one of the registered U2F devices will able to succeed.