Control the ability to login with defguard accounts when using external OIDC

In the OIDC tab -> "External OpenID Settings" section, please add the following option for controling logging in with user/password:

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When external OIDC is enabled, you control if users can/can't also use defguard local accounts (login & password) to log in by selecting a group of users and defining if they can or cannot use local login/password besides external OIDC:

[Dropdown options:]
- All users can also use login/password
- The following groups CAN login with login/password
- The following groups CAN'T login with login/password

Select groups:
[multi select group]

[Save]