OAUTH Additional claims

Is your feature request related to a problem? Please describe.

We have Identity provider for multiple applications.
We want to have granular access. For that we need additional claims

For example https://www.pgadmin.org/docs/pgadmin4/8.3/oauth2.html
OAUTH2_ADDITIONAL_CLAIMS
Pgadmin example

{
    'OAUTH2_NAME': 'SAP',
    'OAUTH2_DISPLAY_NAME': 'SAP IAS',
    'OAUTH2_CLIENT_ID': '<clientId>',
    'OAUTH2_CLIENT_SECRET': '<clientSecret>',
    'OAUTH2_TOKEN_URL': '<ias base url>oauth2/token',
    'OAUTH2_AUTHORIZATION_URL': '<ias base url>oauth2/authorize',
    'OAUTH2_SERVER_METADATA_URL': '<ias base url>.well-known/openid-configuration',
    'OAUTH2_API_BASE_URL': '<ias base url>',
    'OAUTH2_USERINFO_ENDPOINT': '<ias base url>oauth2/userinfo',
    'OAUTH2_SCOPE': 'openid email profile',
    'OAUTH2_USERNAME_CLAIM': 'email',
    'OAUTH2_ICON': 'fa-sign-in',
    'OAUTH2_BUTTON_COLOR': '#F0AB00'
    'OAUTH2_ADDITIONAL_CLAIMS': {
        'groups': ['pgadmin']
    }
}

Describe the solution you'd like

Introduce additional variables to pass claims

The issue does not name any files or tests; start by locating the existing OAuth configuration and authentication flow in the TypeScript UI. Define what additional claims such as groups should be accepted and how they affect granular access, then verify the behavior with the relevant authentication tests.