(feature) Implement open-feature provider cache for the Java provider

[thomaspoignant]

Requirements

Following this specification available on this page implement a caching system in the java provider.

The provider sources are in the open-feature/java-sdk-contrib: see sources.

Please ping @thomaspoignant for review in the pull request on the contrib repo.

[thomaspoignant]

Closing this issue because we released a new version of the java provider.