Bump ehcache to version 3

[sdudzin]

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Purpose

Upgrades Ehcache to version 3 (version 2 contains security vulnerabilities).

Background Context

This is a bit 'naive' implementation but it does not break the Play API which I think is more important. One big disadvantage is the ehcahce xml configuration which force use of Play API as cache item.

[mkurz]

I am pretty sure this needs more work than just bumping the version.

[sdudzin]

I am pretty sure this needs more work than just bumping the version.

Yes this is also my assumption. However to my surprise compilation did not fail for me and I was not able to run tests (I followed the manual on building), there must be a problem with my environment. So, I opened a draft request to see what checks will fail. I hope this is not much trouble?

[mkurz]

I am pretty sure this needs more work than just bumping the version.

Yes this is also my assumption. However to my surprise compilation did not fail for me and I was not able to run tests (I followed the manual on building), there must be a problem with my environment. I also opened a draft request to see what checks will fail. I hope this is not much trouble?

Not sure what you did locally, but just changing the version number will definitely not work, because Ehcache 3 is hosted under a different groupId than Ehcache 2 (org.ehcache vs net.sf.ehcache), see https://www.ehcache.org/ ("Ehcache 3 Quick Start" vs "Ehcache 2.x Quick Start") and https://repo1.maven.org/maven2/net/sf/ehcache/ehcache/ vs https://repo1.maven.org/maven2/org/ehcache/ehcache/

[sdudzin]

I apologize for the noise. I am ok with closing this PR until it's ready.

[mkurz]

I apologize for the noise. I am ok with closing this PR until it's ready

You can keep it open as draft an push every now and then to validate your changes. However if you don't plan to work on it or give up at some point you probably want to close it.

[sdudzin]

@mkurz , I have made a few changes, please have a look.

[mkurz]

@sdudzin Thanks! Can you rebase against latest main branch and also squash your commits? It does not have to be just one commit, but having commits like "format", "codestyle fixes", etc. are not so nice. You can keep commits for "documentation" and others where it makes sense.
Thanks!

[sdudzin]

@mkurz I rebased and squashed the commits.