`server.session-timeout` was deprecated in 1.3 but still used in a sample
that broke once the support for it was removed. This commit fix the build
by using the expected property.
This commit adds support for automatically configuring Spring Session.
In a web application when both Spring Session and Spring Data Redis
are on the classpath, Spring Session's Redis Http Session support
will be auto-configured. The max inactive interval for Redis-backed
sessions can be configured via the environment using the existing
server.session-timeout property.
Closes gh-2318
