Add Java 22 support

[mraible]

Fixes #25562.

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[mraible]

I think it'd be good to change our build process to test Java 17 and 22. Not sure how to do that.

[mraible]

It looks like Gradle 8.7 only supports building with Java 22, not running with it. From https://docs.gradle.org/current/release-notes.html#support-for-building-projects-with-java-22:

Gradle now supports using Java 22 for compiling, testing, and starting other Java programs. Selecting a language version is done using toolchains.

You cannot run Gradle 8.7 itself with Java 22 because Groovy still needs to support JDK 22. However, future versions are expected to provide this support.