Modify cas logout url,use admin url in keycloak client configuration.

[cnxieyang]

In keycloak client config page.we know.URL to the admin interface of the client. Set this if the client supports the adapter REST API. This REST API allows the auth server to push revocation policies and other administrative tasks. Usually this is set to the base URL of the client.

[Doccrazy]

Thank you for your contribution, and sorry for the late response!

Why is this change necessary? According to the CAS protocol specification:

The message is delivered or the redirection is sent to the URL presented in the service parameter of the original CAS protocol ticket request.

In the context of this plugin, the service parameter is mapped to the redirect URI of the client and logout should thus match the spec. Can you elaborate why the current code fails for your setup? Single Logout is largely untested, so you are likely correct, but I would like to understand the reason behind this change.