Ehcache major version upgrade

Ehcache 2.x is no longer officially maintained by the Java community. Moved DXP internal caching to use Ehcache 3.10.8.

This means any existing ehcache configuration xml files won’t be directly compatible and will likely cause errors or unexpected behavior in the new 3.x environment. Users will need to review and rewrite these configurations according to the new 3.x schema.