add support for building java21 code
https://github.com/apache/incubator-pekko/pull/1023 added java 21 code to our docs. I don't believe that we have support for building this code to see if compiles. We have https://github.com/apache/incubator-pekko/blob/main/project/Jdk9.scala and can look into adding a Java 21 equivalent.
I can do that on weekend, I was planning to open issue like this.
And I think this is a good first issue too
Note: Community who interest this can chips in too.
@He-Pin hi, I want to take this, can you guide me on how to do it?
@naosense https://github.com/apache/incubator-pekko/pull/1072 & https://github.com/apache/incubator-pekko/pull/1054 Can you help check it really works, thanks.
I think we have made enough progress to close this.