Add JDK 22-ea to build matrix

[SethTisue]

I would prefer not to do this until JDK 21 final is out. Then we can drop JDK 20 and add 22-ea instead.

see also scala/scala-dev#852

[SethTisue]

prerequisite: scala/bug#12888

[SethTisue]

• behemoth 1
• behemoth 2
• behemoth 3

steps

• cd /usr/lib/jvm
• sudo curl -O -L 'https://download.java.net/java/early_access/jdk22/20/GPL/openjdk-22-ea+20_linux-x64_bin.tar.gz'
• sudo dtrx -n openjdk-22-ea+20_linux-x64_bin.tar.gz
• sudo rm openjdk-22-ea+20_linux-x64_bin.tar.gz
• sudo chmod -R go+rX openjdk-22-ea+20_linux-x64_bin
• sudo ln -s openjdk-22-ea+20_linux-x64_bin/jdk-22 java-22-openjdk-x64
• ./java-22-openjdk-x64/bin/java -version

openjdk version "22-ea" 2024-03-19
OpenJDK Runtime Environment (build 22-ea+20-1570)
OpenJDK 64-Bit Server VM (build 22-ea+20-1570, mixed mode, sharing)

and then

• make the jobs in Jenkins
• delete the old JDK 20 jobs
• trigger runs
• verify the 2.12.x job picks up the right Java version
  • the job won't actually be green — see Add JDK 21 to build matrix #1666
• verify the 2.13.x job is green
  • https://scala-ci.typesafe.com/job/scala-2.13.x-jdk22-integrate-community-build/

[SethTisue]

2.13.x failures:

• zinc: Unsupported class file major version 66 during shading
• twirl: Unsupported class file major version 66
• play-ws: Java 22 (66) is not supported by the current version of Byte Buddy
• metrics-scala: Java 22 (66) is not supported by the current version of Byte Buddy
• americium: cannot find symbol during javac run, cause not obvious to me

so the only one of these that's a little odd is americium. I'll report it to the maintainers (sageserpent-open/americium#67). and I'll mark of all these as expected-to-fail (commit: 338218f)

[SethTisue]

heh, oops, somehow the Jenkins jobs were still on 21. fixed, but nothing new turned up but a new metals test failure (a too-fragile test) I reported upstream