Upgrade to Spring Session 4.0.1.

Comment From: mrksph

Spring Session 4.0 reference doc is returning 404.

https://docs.spring.io/spring-session/reference/4.0/index.html

Comment From: philwebb

Thanks @mrksph, I see you've raised https://github.com/spring-projects/spring-session/issues/3511. We'll have to wait for a response on that issue.