First factor_type always selected if factor set in .okta-aws config

[mdietz]

Describe the bug
If there are multiple valid factor_types supported by a given provider, the first is always selected if a factor is set in the ~/.okta-awsconfig file:

okta-awscli/oktaawscli/okta_auth_mfa_base.py

Line 62 in 42681a7

factor_choice = index

.

To Reproduce

1. Set factor = OKTA in .okta-aws file.
2. Run okta-awscli as a user with Okta Verify enabled but Okta Verify push notifications disabled as a valid factor.
3. okta-awscli blocks on "Waiting for push verification..." but no push is sent.

Expected behavior
Either:

1. okta-awscli gracefully handles the Okta response (I'm making an assumption that Okta will respond that it cannot send a push notification if that's a disabled factor for the user) and falls back to Okta Verify TOTP.
2. Allow a factor_type to be specified in the config file.

Environment (please complete the following information):

• OS: MacOS