Surrogate auth support in oidc password flow

[Andrea Maria Farina]

Hello,

I would like to contribute to the project by adding support for surrogate authentication in the OIDC password flow. I’ve noticed that the surrogate credential pattern, "surrogate+admin," is not currently supported when using this flow.

I have already made changes to the code from the 7.1.x branch and am testing them in the development environment.

You can review the changes here: https://github.com/apereo/cas/compare/7.1.x...TheAndrewSAMA:cas:7.1.x

Best regards,
Andrea Maria Farina