doc: add references to java 21 image

[sparsick]

I saw that you already support Java 21 but this is not mention in the documentation.

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[loosebazooka]

We're not quite at the point to finalize java21. There are a few minor details to work out

[mkarg]

Any news on the Java 21 topic? :-)

[mkarg]

@sparsick So finally your PR got approved, but meanwhile it is conflicting. Kindly asking you to resolve, so it can finally get merged with the main branch. :-)

[sparsick]

@mkarg Thanks for mentioning. It is resolved.

[mkarg]

@mkarg Thanks for mentioning. It is resolved.

@sparsick Thank you for your quick resolution! ❤️

@andrzejsydor Kindly requesting merge. 🙏

[loosebazooka]

FYI @andrzejsydor is not a project maintainer. Not really sure why they keep approving PRs here.

[mkarg]

FYI @andrzejsydor is not a project maintainer. Not really sure why they keep approving PRs here.

Understood.

So kindly requesting your review / merge instead! :-)

[loosebazooka]

We're still not fully stabilized on the java21 image. I understand that we're going slow here, but you're welcome to use it before then.

[mkarg]

Anything volunteers could help here?

[ranma2913]

@mkarg @loosebazooka What's left to do on this? I can help and would love to be able to start using the Java21 image.

[loosebazooka]

I think we're ready to merge this, just want to make it explicit that we're using temurin