Customize validations for the OIDCAgentConfig.

[chamathns]

Description:
Add Validator implementations in the SDK for validating the Agent Config in order to add customizable validations and enforcement.

public Interface Validator {

     void validate(OIDCAgentConfig config);
}

validators - CodeValidator, LogoutValidator, ImplicitValidator, etc.

public OIDCManagerImpl(OIDCAgentConfig oidcAgentConfig, Validator[] validators) throws SSOAgentClientException {
        
        for (Validator validator: validators) {
            validator.validate(oidcAgentConfig);
        }
        this.oidcAgentConfig = oidcAgentConfig;
    }