Update versions of other actions in README example

[ghost]

I noticed that these were out of date and I figure it couldn’t hurt to
keep the ancillary aspects of the example up to date, just in case
people copy-pasta the whole example.

Speaking of which, I was also tempted to add cache: maven to
the setup-java args since it seems like a good default to me, but
I held off just to keep this change focused on one specific kind of
change. That said, I do think that’d be a good idea.

[DeLaGuardo]

cache: maven might be good addition however it only looks at **/pom.xml which is not all the time connected with clojure-based projects. Maybe it could be a good idea to file a PR for setup-java action asking to support either custom value for cache input or add support clojure-based projects in general.

Anyway, thanks for your contribution