fix(datahub-frontend): Add playCaffeine as replacement for removed playEhcache dependency

[MideO]

Checklist

• The PR conforms to DataHub's Contributing Guideline (particularly Commit Message Format)
• Links to related issues (if applicable)
• Tests for the changes have been added/updated (if applicable)
• Docs related to the changes have been added/updated (if applicable). If a new feature has been added a Usage Guide has been added for the same.
• For any breaking change/potential downtime/deprecation/big changes an entry has been made in Updating DataHub

This is to resolve the issue described in #7733

[RyanHolstien]

The EhCache implementation is deprecated and considered legacy, can this be done using the play Caffeine impl?: https://mvnrepository.com/artifact/com.typesafe.play/play-caffeine-cache

See:
Play provides a CacheApi implementation based on [Caffeine](https://github.com/ben-manes/caffeine/) and a legacy implementation based on [Ehcache 2.x](http://www.ehcache.org/). For in-process caching Caffeine is typically the best choice. If you need distributed caching, there are third-party plugins for [memcached](https://github.com/mumoshu/play2-memcached) and [redis](https://github.com/KarelCemus/play-redis).

https://www.playframework.com/documentation/2.8.x/ScalaCache

[MideO]

@RyanHolstien Thanks for the feedback, I've replaced play Ehcache with Caffeine.

[RyanHolstien]

This looks good to me, just waiting on CI to be green. We're actively working on fixing some flakiness so hoping your PR can get in after that.

[MideO]

bump @iprentic @RyanHolstien please can we get this merged in?