Support pinning java-version as `"latest"`

[aep-sunlife]

Description:

As a developer, I want to create a GitHub Actions job that tests my JVM projects against floating, bleeding edge Java versions. For comparison, workflows for other languages like Go support this with the "latest" version value.

Justification:

Today, I do not see an option to let the Java version automatically target the latest stable Java release version. Which breaks efforts at futureproof testing, with each new major release of Java.

[mahabaleshwars]

Hi @aep-sunlife,
Thank you for creating this feature request. We will investigate it and provide feedback as soon as we have some updates.