Verifies a code against a challenge. The verification code is provided by the user by entering a code seen in their authenticator app.
final res = await supabase.auth.mfa.verify(
factorId: '34e770dd-9ff9-416c-87fa-43b31d7ef225',
challengeId: '4034ae6f-a8ce-4fb5-8ee5-69a5863a7c15',
code: '123456',
);